I've tuned up quite a few MTBs from this era, which of course means test riding afterwards. My favorite so far is my 1993 Giant ATX 780. Nice light frame, 1 1/8" headset means I can throw on a suspension fork if I wish, and a total blast to ride. My early 2000's Gary Fisher Ziggurat felt similar, though with an aluminum frame. Behind those two, I had a '95 Fuji Discovery rode nicely, but had a 1" headtube, and a '93-ish GT Pantera was probably my favorite out of what I've done at work. My goal is try to ride at least one bike from each major brand of this era and see if anything surpasses my Giant, and if that ever happens, might be on the lookout for another frame.