the guitar is about 9-10 years old. it's a used paul gilbert model 30, with the lo-trs tremolo (not floyd rose). the seller is asking $550 for it, but i hardly think that it's worth that much. what do you guys think?
Save that $550 for a PGM301.
The 30s are just like the JS100s and JEM555s, just don't bother.

Either save for a PGM301 or buy a prestige Ibanez (may need to save a bit of go used)
or preferably an RG 550, 570 etc etc (you'll need to go used but it's worth it).
Too much money for a guitar with a Lo-Trs. I can tell you from experience that it does not stay in tune and is inferior to the Edge and Floyd Rose. RG550 is a very good alternative but you'll have to save a bit more.
honestly i'll probably never use the trem and isn't it directly replaceable with a FR bridge anyway?