My neighbors have a fabric arena and I've ridden in it.
The supports on the walls are slanted metal, so either you put up kickwalls and lose a good 4-5ft of space or you run the risk of decapitating yourself while riding. Neighbors chose the decapitation risk since all they have is mostly dead, quiet horses. My trainer ended up lining all the walls with chairs, barrels, folding tables and whatever else she could find since my horse is young, green and spooky...... only he was terrified off all the "stuff" so it was an interesting ride.
Light and Airy = every last shift in the clouds over the sun, bird flying overhead, plane overhead or whatever = spooky, shifting shadows. Again, if your horse is mostly dead, no big deal. Young and green? Not so wonderful...
Personally, I'd go with a metal one. Snow shifting is scarier in a fabric arena and because it's fabric, you can't take a really long pole/brush and go remove it before riding. Around here the folks with metal arenas take a broom on a long pole and brush off the roof.
Oh and metal buildings depreciating over 5 years? Please come inform everyone around here of that I've been shopping for a used one and everyone wants almost the original cost for their OLD building and people ARE buying them!