Guess I'm old school, 'cause I like ebonite. I clench, too, but the lucite doesn't deter me from that...a bit harder, but if it was uncomfortable, I'd never have bought another one after my first. I do find ebonite more easily held and softer, though.
The oxidation (my pipes were bought new, and I've only had them for a little over a year) issue doesn't bother me. I apply bamboo oil (or mineral oil) to seal them a couple a times per year, so that helps. I always clean clean them whilst smoking and wipe them down with a Briar Wipe impregnated cloth after I'm done.
I've cleaned up a couple of pipes for someone once. They were from the '50's and heavily oxidized and toothed up. I used fine grit wet sandpaper and got most of the teeth marks out and some of the discoloration (wasn't really trying too hard on the oxidation...old pipe and all, for him it was part of the attraction).
I've also modified the fit on some of my lucite and ebonite stems (a little snug) by also using fine wet sandpaper and finishing with a plastic polish (like for cars). I wouldn't be amiss to using the polish on any stem that started to discolor.
Originally I didn't like lucite at all, especially the colored stems. They didn't look like "pipe" stems to me. Well, after you buy a freehand or two...they don't really look like "pipes"! So, what's the big deal w/the lucite....