As an A4000T owner with a CSPPC I am partial to that, but if you only plan to use 68k stuff and dont care about the PPC side of things you can look for a CS MKIII. Both are identical in terms of 68k operation.
If you can find the Quickpack 060 board that came in the last of the 4000T machines they produced I would grab one for sure over a MKIII.