Ok, so I got these RIGHT before Irma. I mean, literally at the 11th hour. I actually paid extra over regular Prime shipping to have them Overnighted and for some dastardly reason whomever shipped them put signature required on the low-value package and I MISSED the delivery and was not able to pick them up at my local UPS until the next day which was super-stressful, and only possible because the storm slowed down and changed course enough that it bought me the time to still deploy them. None of this is the fault of the product itself, of course, I only mention it here in case anyone else is in a similar situation and is ordering them last minute, be careful about that signature-required pitfall for overnight shipments. *Amazon did refund the extra I paid for overnight shipping.* As for the product itself, I waver between giving it four or five stars. I decided to give it the benefit of the doubt and give it 5 for now, because the minor insufficiencies I detect in the product MAY be due to my user error. It did not swell up evenly along its entire length, despite the fact that the entire length was definitely heavily rained on. I used them for my two-car garage door, my back porch, and to protect a feed room in a barn. None of these 3 locations have experienced actual water intrusion in the past, however, I have had water inch frighteningly close in past storms, and with images of Harvey fresh on my mind, I knew if we had anything even approaching half of what Harvey was, I was in for some deep trouble. Turns out, other than just the typical puddling I get in these areas, there was no real flooding threat from Irma for my area. So, although I can't boast that these Quick Dams saved my property from a great flood, I can testify that they do work because everywhere that I put them, they did stop what water there was from passing through them. I am just slightly concerned/puzzled about the parts that did not swell. Would they have swelled if the flooding had been more substantial? Or is that part of the dam defective? I don't know. I did read in a review on another one of this manufacturer's products that you should wet the dam with a hose first before use. The manufacturer includes NO instructions in the box, so I don't know if this makes a difference or not. Water is water, right? I will add the following tip that if you are expecting a flash flood, weighting down the ends of these dams with sandbags or cement blocks is a must, because they are very light, and I could see them being swept/blown away before they absorb enough water to be heavy enough to stay put. So, in that context, I would believe that wetting them down first is a good idea. But, again, I don't know about the failure of some parts of my dams to swell as I would think they should. Another insider tip, I had posted the question to the manufacturer if these dams could be cut to fit. I got the short answer "No, they can't, that will ruin them." Well, I had an extra and could afford to risk one, so I did. I of course double stitched a channel at the cut point before cutting it in half. I can confirm that cutting them in half does not ruin them and they work as normal. It is possible that the manufacturer's representative assumed that I did not have the ability to sew the ends and thought I was going to just cut one in half which I guess would allow the hydrophilic powder to leak out. Hence the apparent misinformation. I am currently using the short piece I cut under a stall door at the end of my barn aisle that frequently gets water leaking in from horses being hosed off at the washrack adjacent to it. For that alone, it works great and is a better solution to anything else I have found in 20 years of dealing with that problem. So that was my second reason to tip my review in favor of 5 stars for this product. Final point I'll make: be aware these dams aren't that high. When fully expanded it looks like they would keep no more than 2 or 3 inches of water out. As we all know, that alone can be a lifesaver. But don't count on them handling any more than that. I don't know why, but I was expecting them to be taller based on the pictures. Guess that was just my misconception. I wouldn't so much call them "flood control dams" as I would "creeping water dams". If I ever use them in a subsequent water event, I will update my review accordingly.