well the problem is the track limitations on both. with liquid mix im limited to 32 instances (both can contain eq AND compressor) so they'll basically be my channel strips.
the uad2 will run about 20 of the neve88rs channel strip, so 8-10 of them will cover my mix busses and groups while still leaving room for a few plate140s (essential) and other bits and bobs (like la2a for the bass and 1176 for the overheads)
anything after that (special fx etc) will be run nativly and if i need to go over the 32 audio channels that liquid mix will give me then i have the mcdsp compressor and eq banks, which are a similiar idea to liquid mix emulations but in native format.
also in the future i plan to get uad's new ssl emulations. having the scope to run a virtual ssl or neve desk is very appealing to me at the moment. ive tried this a few times and i find a consitant plugin chain on each channel can add a lot of glue to a mix and make everything sit together a little better while still having the option of throwing some extras in to spice things up a little.