OK so I've sort of had all 3, although I have the old Teutonia T-260 (with 3 tires) rather than the 460. I only used the Cam twice outside as I bought it to resell (sad to part with it, however!)
I think you need to think about how you will use it. I really feel like the Vista is the best for a new baby. I loved the bassinet but I only used it on the stroller for about 6 weeks (I used regular seat with Snugseat insert after that), but it was also DS3's bed that he slept in every night until he moved out of our room at about 4 mos--which would not have been possible with the Cam unless I bought another frame. The canopy is great. The huge basket is wonderful and if you think you will use that feature it is worth it. Since the seat is high you have your newborn "close to you".
The suspension and steering is loads better on the Cam and personally I felt the Teutonia had the best suspension of all. And even though the Vista is in actuality only a little wider than both the Cam and the Teutonia, it feels a lot bigger, probably because of the high seat. I know some have said they love it higher because, for example, they can pull the stroller up to a restaurant table and the child will be at table-level, but personally I've felt like waitstaff etc. cringe when they see me haul that thing into a restaurant compared to a seemingly more reasonably sized Cam or Teutonia.
So, I guess what I am saying is, DS3 would be fine in the Vista still, but at 8 months I no longer need the newborn-friendly features of that stroller. So it is not really my fave any more because I would rather have the better steering. It still has the advantage of the better canopy and better basket, (and adjustable footrest) compared to the Cam, so if you feel those features are more important long-term than the push, I would go with the Vista. If you value the better push, reversible handlebar, slightly smaller footprint of the Cam, and can deal with the fold, I would go with that.
As for the fold/unfold, I haven't seen a T-460 IRL so I don't know how bulky it is. I hated the Cam fold. 2 piece but also just "wonky" to open it back up for lack of a better word. T-260 fold is 2-piece so still not great but the frame is super easy to open and close. Vista is best I guess since it's 1 piece facing forward. IMO Teutonia T-460 would seem to be a good bet as it has great suspension and reversible handle like a Cam but also good canopy, peekaboo window, and a completely separate, nice-sized bassinet like the Vista (not a great basket though). But if the fold is a dealbreaker in your case then, honestly either Cam or Vista would be fine, just think what particular features of each are most important for you assuming you want to keep the stroller for a long time.
M, Mom to 3 handsome boys, '06, '08, '11