Hmmm. Interesting points. For the moment the wedge I am using as my bass cab at rehearsals is working a treat. No farting, distortion or any nasty side-effects. I can't imagine I'll have any other real use for it, so I'm not too worried about damaging it.
In the long term I expect I will add a second "proper" bass cab and retire the wedge, but for the moment it's definately doing a job for me, and I don't mind schlepping it around, banging it about etc, as it has a tough as nails plastic outer, and it is saving use, and wear on my RS112, which I will add in to the rig for gigs only.
Also, just a comment on the "wedges angled up are no real use for bass" idea. SUrely, the actual frequencies that cut through, and also tell us as a player what note we are playing, are not the real bass frequencies, but much more in the midrange, so surely angling the cab up at you does significantly help you hear those key frequencies, despite having no effect on our hearing of the real low bass frequencies.