If you buy a lift, then you'll want a router motor that fits the lift. The Bosch 1617 motor and PC 690 motor both are 3.5" diameter, which is one of the standard lift sizes. As Mike said, the Bosch plunge base is not designed for table mount, but the fixed base is great and allows for above the table adjustment without a lift. (yes, you have to reach under to clamp/unclamp the base). For the cost of a lift, you could pick up a second 1617 with a fixed base and a Musclechuck (for above table bit changes).
Your needs/wants may be different than mine--but when faced with that question i picked up a second router kit (1617EVSPK) instead of a lift. No regrets at all!!