Works as advertised. Unlike some others' experiences, mine didn't leak at all -- at least not on the first use. UPDATE: After using this for the first time (except for an initial test with plain water, after which I wrote my original comments, above), I have to reduce my rating from very good to OK. Why? Well, the worst problems seem to stem from the quick release when using the sprayer the conventional way (with the provided container). If you hold the unit too far back, you risk having the quick disconnect release the sprayer, which then falls to the ground. In my case when that happened, it hit dirt, and so the connector and o-ring seal were a mess. I cleaned it, but evidently not enough, because after that happened the level of concentrate in the container didn't seem to go down. Also, I had to force the quick disconnect together because the hose was still under pressure. After a while I increased the spray rate from 1-1/2 teaspoons (the recommended amount) to 4 teaspoons, just to see if any concentrate was coming out, and the level inside the container still didn't go down! I concluded at that point that I'd been spraying plain water instead of the product that I was trying to spread around the yard. What was the problem? Well, I found out that in order to get a decent seal with the quick disconnect, the water pressure in the hose has to be zero. Otherwise, it appears that the seal is imperfect and air gets sucked through the quick disconnect, preventing concentrate from being drawn up into the sprayer head. When I removed the quick disconnect that way (releasing the pressure in the hose), I also cleaned the connecting parts very thoroughly. Then I re-attached the hose, and turned the water back on at the hose bib. Now the level of concentrate seemed to go down inside the container as I sprayed. Even though I was very careful, the quick disconnect came apart a second time. This time it didn't fall in dirt, thankfully, but I did have to de-pressurize the hose to re-attach it and get a good seal. And then turn the pressure back on. Then the concentrate level went down again. But I had to re-do an entire part of my yard that had been sprayed with plain water before I figured the quick disconnect out. One good thing about the quick disconnect is that it allows the unit to swivel and be vertical even if the hose wants to twist a different direction. That's a plus. But you really have to remember to hold the unit very close to the handle in order to try to prevent the disconnect from releasing. The other thing that bothers me a little is that I'm not sure if this sprayer is measuring the amount of concentrate per gallon properly. With my old-fashioned Ortho sprayer, I used to go though about twice as much concentrate to cover my yard. Maybe it's just that the sprayer puts out less volume, but I can't tell. I do like that it sprays with large droplets, which are far less likely to blow in the wind (and into my face) like the old Ortho did, so that's a plus. Anyway, three stars, not four. UPDATE added August 20: No, not three stars, just one. Today was the second time I used this sprayer. It was leaking profusely at the connection to the sprayer. I thought maybe it needed a new rubber washer. (They don't use a rubber washer, it turns out.) So I tried to unscrew the connection to the sprayer. It just turned, and wouldn't unscrew! To get it off, I had to pry with a screwdriver (not recommended because I managed to stab myself in the process). Then I tried to screw it back on, and that wouldn't work because I'd damaged the threads getting it off. Into the trash it went, and I used my old Ortho Dial-a-Spray hose-end sprayer instead, which still works fine. (The spring on the trigger is gone, but that's ok, I just move it back into the off position manually.) I wish Ortho still sold those, rather than the bulky "ergonomic" version they offer now. So my suggestion now is: DON'T BUY THIS CHEAP PIECE OF JUNK. You'll waste your money, your time, and patience.
