If it's not too expensive, get it.
Real nice vintage twins.
No real collectibility, though, and not rare or anything.
The only 450's with any sort of collectability are the old 4-speeds, the Police models, and the "D"-models.
Easy to work on and dependable, once you give it good compression.
So, an investment?? No.
Loads of fun and high coolness factor - oh yeah.