Frank, I've done the seam sealant with an ATC approved product. It stopped the leakage through the stitches, but the water still accumulates between the mesh and the clear plastic and runs along that bottom seam until it comes out either end.
I'm late to this but this is exactly my experience too... very frustrating. I like the idea of the flaps but the implementation isn't great. I've put some aquaseal on the stitching and along that seam Vic speaks of. Haven't had rain in a while so haven't been able to test my "fix" yet. I also tried to get some of the sealant down along the bottom seam next to the clear flap.
BTW, the other downside to this is that you have plan ahead (like Vic pointed out) if it's going to rain, etc. We also had to buy a lightweight, ladder as our truck is pretty high and I can't reach the top velcro to put the flaps on (usually during a rain storm when I didn't plan ahead). Also, with those flaps on, you have no way to get ventilation (or you have to go back outside and un-velcro a portion of the flap). It can get really stuffy.
I guess what I'm saying is, that I like the old method better. More control, always on, etc., etc. BTW, this is a replacement vinyl on our 2001 Eagle (we use it a lot) and this was the only option (from ATC at the time).
Edited by kmcintyre, 01 September 2021 - 10:29 AM.