I have no experience with this company. However I do have quite a bit of experience with suction cups, and it's not good. I have seen these being sold at different gatherings so I'm pretty sure we are talking about the same thing. A couple years ago I made my own and used suction cups just like the ones that come with these kits. The suction cups work very well for a while then start to fail depending on how hot it is outside. I have found that Hi-temp velcro works very well attaching to glass and so far has not failed. You can make your own like I have or you can buy theirs, throw the suction cups away and use Hi-temp velcro (Graingers).
Aero AT4040XL, AFE, Koni FSD,
Source Eng. Trailing Arms