I like trying new things and picking the one I like the best of a variety of reasons.
Brett Lewis should be here, I am about to affirm his statement about things looking pretty - I found a ROM that has it all, stability, speed, *and* aesthetics - the glass on this ROM is *only* outdone (thus far) by the Blue Smoked Glass theme that Pete used for a bit, before I switched over to SG4.5
In the end, though, it's personal choice - that is why there are 152,567 different 'versions' of *ix out there, with another one being released every 19.63 minutes....