I've read they are both good products. I've only used Red Guard once, availability was the reason for the choice. My go to is normally a sheet membrane or a board product. Time is the reason for going to the board products (Wedi or Kerdi board).
Haven't used any, guys have told me they are good but I'm leery. I don't use anything that makes me worry about a call back. When needed I install Schluter or Noble membranes. Durock or Densarmor are good wall boards.
I realize the whole water proofing membrane thing is huge now. I'm big on using the right products and installations. However, unless you are talking about specific water heavy installations a lot of this is overblown hype to sell product. Regular shower use normal installation; Steam shower obviously you'd want membrane.
Hydro ban, that's what my supplier has in stock, and I've never had a problem with it.
Easy application with a paint roller, no fumes that I recall, decent coverage.
Dries fairly quickly.
I'm a happy guy !