I looked at the published R-values of this product and NASA Tech. They are both broadly listed as R-21. There are better insulating products available usually of the fiberglass batt type but these can be "dirty" and difficult products to install. The NASA Tech originally looked like the best bet but to install it, I would have had to remove the hurricane straps (5 of them), unroll the NASA Tech, marking the holes where the hurricane straps were bolted and reinstall the hurricane straps and bolts. Not a small job. I elected to purchase Reach Barrier becasue of the pre-cut panels. First, one box covers a single car garage door. For my project I needed two boxes for a 7'h X 16'w door. Second, each panel in the Reach Barrier Kit is 24" X 48". There's enough product to do 16, 24" X 24" panels per box Third, not every panel on my garage door (an Amarr Product) is the same size. The outside panels (closest to the roller tracks) are 25" wide, 21" high. The others are all 23"w X 21"h. Each panel had to be trimmed from the stock panels in the kit. I started the project by myself by marking the dimensions with a marker, labeled the L corner and top of each trimmed panel and would trim the stock panels to size using a long straight edge (a level) and box cutter. The panels trim neatly and easily with a box cutter. I switched to one person cutting (my wife) and the other (me) installing it - that saved a lot of getting up and down from one's knees. The first 4 or so panels cut and installed solo were slow going; it took about 10-15 minutes each panel to trim and install it. Going slow like this with one person doing the cutting and installing would take almost 3h to do one half of this project, 6h total. Too long. Get the wife, save my knees! Once we got a system going we did the other 28 panels in about 90 minutes. They advantage of the Reach Barrier product over the NASA tech is that I was able to install the cut panels without removing the hurricane straps. If you look closely at the photos of the completed garage door, you may note that the hurricane straps will actually hold some of the panels in place (there is enough space between the aluminum panels and the hurricane straps to easily work the cut panels under them). I started out using the stickies per the instructions. The problem with that was installing the stickies on the panel, removing the top covering of each of them then trying to slide a panel under a hurricane strap without the panel sticking to them until in place. After screwing up one panel that way I stopped putting the stickies on all four corners and in the middle. Instead I started cutting the panels 1/4 " longer in each dimension. Voi-la. They fit snuggly in place (mostly). If there was a saggy corner, I'd put a sticky under it by rolling the corner back, placing the sticky then unrolling the corner onto the sticky. That was only required on a couple of panels. The design of the door made it possible to jab that 1/4" extra of material in a grove and it stayed in that grove even with the door operating multiple times to test this technique. I imagine that wouldn't work on some door designs with or without Hurricane straps and you'd have to use the sticky is The important thing for DIY'ers is that you can easily install this product successfully even when leaving horizontal hurricane straps on the door. As for performance, I'm impressed so far. My garage door faces west and in the afternoon the door gets blazing hot - likely over 110 degrees. The garage is uninhabitable in the heat of the day with inside garage temps reaching 102 - 103 and it is presently serving as a storage area for heat sensitive things. I'd estimate that the insulation alone drops the ambient temperature inside the garage 8-10 degrees in the heat of the day with full sun on the door. Low 90s is still uncomfortable. My garage is about 450 SqFt. I just installed a 10000 BTU portable room AC that ducts (intake and exhaust) out the garage window. With it set at 80 degrees, it has no problem getting the ambient temp down to just under 80 degrees - comfortable for us. In the heat of the FL sun, the combo of a portable AC and the garage door insulated with the Reach Barrier product makes the garage a useable space. All I need now is a solar shade for the 48" X 48" window that I noted today leaks a lot of radiant heat now that the garage door isn't doing that!.