We went with vinyl too, and yeah, noise reduction was noticeable. But honestly, the savings on heating and cooling weren't as dramatic as some people make it sound. Maybe it's because our old windows weren't in terrible shape to begin with, or maybe our insulation is just average... who knows.
I do agree wood frames can be a pain maintenance-wise, but I still think they have their place. Vinyl's practical, sure, but it doesn't always match the character of older homes. We have a neighbor who refinished their original wood frames instead of replacing them—took some elbow grease, but they look amazing now. And from what they've said, their energy bills improved quite a bit too.
Guess it depends on your priorities and how much you're willing to spend upfront versus long-term savings. Vinyl's great for convenience, but if aesthetics matter a lot to you (and you're handy enough), restoring wood might not be such a bad option either.