Update 2/11/2021: I was able to repurchase this watch at a very, very reasonable price - all things considered. Given that I got it for under $500 I must say it's incredibly impressive, even without a great HR sensor. I have grown used to using my HR strap for workouts at this point and the training suggestions this watch makes based on that information is truly amazing. I am a strength and conditioning coach and I am extremely impressed that under the calendar widget they added a new feature of recommended workouts for running and cycling for each day based on previous workouts and the HR data. I'd say it's spot on with how I'm feeling. It's very, VERY good. The battery life is still excellent. I get about 11 days with 1hr of training each day. I do not sleep with it on. I love it at this point and am pleased that I found it at a lesser price. It's worth it. 4 stars for the mediocre HR sensor and high price. UPDATE: 5/11/2020: So, I have given up on this watches HR tracking ability. This one issue is significant and it really is an inconvenience to always have to look for and use a chest strap. I have extensively, over the course of 8 months tested and re-tested this device in hopes that the HR accuracy would improve with time. It really hasn't. In short, so you don't have to read everything else I posted her, it straight up sucks when compared to the apple watch 4 or 5. This watch cannot accurately display your HR when ascending hills on a walk. On a hike, they finally got something to register. Up until the last update, it would never crack 89bpm. Now, if you're working hard ascending a hill, it will eventually catch up and display a HR that is accurate but the lag time to get there is insanely long. Usually 30 seconds or more so you'll be done with a hill and on flat ground before it catches up to, and displays it correctly. It will not measure HR correctly on bike rides on anything but flat, smooth terrain. It only works when steady state running or steady state bike riding indoors. All of the training effects/suggestions are based on HR data. This does not record HR data accurately or at all in most cases so that stuff is useless in practice. I would not buy this. It is way to expensive. You could buy it and use a chest strap for all activities which is up to you to decide if spending this much and having to use that is reasonable. The apple watch 4 or 5 are still far superior. I thought I'd use the maps feature more and I do find it incredibly useful, but because I train the way I do, having solid HR tracking is more important to me than the map features which I could probably find a solution for via my phone. I train everyday with lifting, running, cycling, swimming or some variation of HIIT training. Keep track of the HR data is a great way to see how my fitness is progressing. Don't waste your money on this unless you don't care about HR data. Other than that it's dope, but it does not work as advertised in a hugely important way. I can't overstate that enough. This is supposed to be a fitness tracker, after all. TL;DR as of 2/10/20 I would not recommend buying this watch. There has been a persistent issue with the HR monitor either lagging behind excessively or not properly reflecting your HR during several activties including hiking, stair workouts and others. Garmin knows of this issue but hasn't fixed it and I've been waiting months for that to occur. I am returning this watch and waiting for a fix at which point I will repurchase it or waiting for the 7. I'm an Ironman triathlete and outdoorsman. I've been seeking a fitness tracking watch for the past year to replace my Apple Watch Series 4 since it is inadequate is some areas: in particular, battery life and the lack of an always on display. This review has been ongoing and I keep updating it with more experiences. I am definitely disappointed with a few very specific and important features. I will elaborate in an update section. I had previously tried three Fenix 5x models. All 3 had an optical HR sensor that was atrocious and I thought it could be due to a faulty unit, but it's just their inherent design. You can google this independently and conclude the same. The sensor was always delayed during cycling workouts and failed to reflect my heart rate as it dropped when I rested from intervals. The Fenix 6 is a substantial upgrade in every category compared to the 5X. However, my focus of this review is on the heart rate accuracy and if it is better than the 5x. I tried this unit out because Garmin redesigned the sensor for the new Fenix 6 models. I can tell you from personal experience that it is better at locking into a HR when compared to the 5X. It is still delayed when compared to the apple watch series 4 and 5 or a wahoo tickr chest strap. It usually takes about 10 seconds after a 5-10 minute warm up to properly lock onto a HR. All is good once it locks in and it’s usually only 2-10 seconds behind a chest strap and at most, 2-3 beats off from the chest strap but it actually matches it most of the time. It's excellent at steady state activity like longer runs and indoor cycling on a trainer but that seems to be about it. The biggest problem that persists which was present in the 5x, is the inability for this device to accurately display your heart rate as it ascends or descends if you quickly change intensity, or come to a stop to rest from any type of interval workout - or any workout for that matter. Especially outdoor cycling because of the vibration in the road. In other words, if say, you were to do a quarter mile hill sprint on a bike, there is never a time when I stopped that the watch was able to reflect the descending heart rate properly. It would usually hit 165 then, it would slowly drop and get stuck at 110-120bpm, when in reality compared to the chest strap or apple watch series 4, my heart rate was at 75-90bpm or less. I sometimes would wait up to seven minutes before the watch would reflect the lower heart rate. This renders any short duration activity useless. It distorts the displayed training effects (if the workout was primarily aerobic or anerobic once you hit stop) and turns your workouts and post workout training effects that are displayed into garbage because your average heart rates are entirely thrown off usually 20-30 beats too high. This renders the device useless for anyone who weighs interval training heart rate data heavily in their training program. Unless you spend another 75-100 for an external strap which should not be necessary at this price point. I want to make this very clear: the Apple watch 3 and beyond have been scientifically researched in a few medical journals and have been shown to be the most accurate wrist based optical heart rate sensors when compared to Garmin, fitbit and one other brand I cannot recall. This is extremely troubling to me because Garmin advertises itself as being the gold standard for fitness enthusiasts. This is a major shortcoming that cannot be overlooked in a nearly one thousand dollar time piece geared to help you train more efficiently. For that reason, and that reason alone, I would not recommend it. Garmin's main competitor in this space (Apple) can make a product that yields accurate data for 50% the cost. However, I will say that the watch has many other features that are outstanding including its display which is remarkably easy to see in the light and 60hrs of GPS tracking for long overnight backpacking trips or endurance races/workouts. Based on my current experiences, the navigation ability is good and its usually about 50 feet off from my target destination which is impressive. It's tough to swallow buying a watch this expensive and it not being at least as good as a year or older Apple watch heart rate sensor. It just isn't. It is terrible for elliptical and hiking workouts and takes 5-10 minutes to lock in and usually fails to at all because of the arm movement, it is just terrible during
