I've owned T2 for a long time and don't see that changing. T3 is a better game. It's 12 years newer, deeper, and has better sound. The RPG isn't any less annoying than the T2 video mode.
If you had to pick one or had a small collection, I'd say pick the T3 unless you have some nostalgia attached to the T2 (like me). However, If you can swing it I'd get the T2, play it for six months, then sell it and get a T3.
T2 is the first game I pumped a ton of quarters through. And, the Sterns just don't "feel" as good to me...but maybe it's in my head. That's why I have a T2.