Sound quality in PerfectSpace is equal to any other convolution reverb, and it's quite full-featured. The only downside to PerfectSpace versus others is that it's not a true stereo reverb. IOW, the inputs are summed and then the delayed copies are randomly panned. This isn't as much of a limitation as it sounds, and many reverbs (both convolution and algorithmic) work this way.
However, I'd think that one exception where it
might be a limitation would be small ensembles of acoustical instruments, where preserving panoramic subtleties could be more important. You might therefore want to take a look at Voxengo's
Pristine Space, big brother to PerfectSpace. At $120 it's not particularly cheap, but it does offer true stereo operation.