New Turbo on - still sluggish on hills - fuel?

The wear on your replaced turbo could indicate a problem with the air cleaner, which could also produce wear on other engine parts such as rings, etc. and lead to reduced power levels. Such wear would show up on the cold side of the turbo, not the hot side.

I would make sure the air cleaner and its related tubing and connections are in good shape and not leaking. Also, an oil sample sent to Blackstone Labs at your next oil change can tell you of any such problems for about 30 bucks.