I migrated to the TA setup because I thought I would have more flexibility with layout (no big gaps in between rails, etc). It was between this at Rockboard, but TA won out because it's a little more popular and I read, at the time, enough good things to convince me. What I really like about the TA setup is the modules. Board-mounted power cable input with on/off switch, input and output jacks. I know there's aftermarket stuff to make this happen with a Pedaltrain, but they're not ideal and I don't really want to have to drill holes to mount them.
Dual Lock is great for under the board. I tried it on top of a homemade Nano once, but two strips across was too strong. I've now learned there are different strengths of Dual Lock, so maybe the slightly weaker hold would work better. I like the security and cleanliness of the TA setup, and the hassle of changing things up has slowed down my flipping habits for the better, but I'm over it at this point.
That's the stuff that's not "sticky," right? Are people really using it for boards? I'm intrigued, but I imagine it's probably even more of a cat hair magnet than Velcro.