I also have a Porter Cable 1 3/4 HP (693) router with interchangeable
plunge and fixed bases. I have the opportunity of getting a Milwaukee
3 1/2 HP fixed base (5625-20) router for a very good price and am
wondering if it offers enough of an advantage that having both would
make sense.

I have 4 routers, all bought at a good price, and all different. (Two DW,
two PC.) It's great get most of the waste out of the way with a straight
bit, then pick up the router with the dovetail bit.

However....

Instead of 4 different routers I wish I had 3 DW 621's. Then the jigs would
work on all my routers. ;-)

-- Mark