Even though you already pulled the trigger, I think this statement of yours right here clarifies matters pretty well:
"Or should I buy the mortiser for what may possible be the largest mortising project I ever do even though my wife loves mission style furniture"
You will be building a lot of mission furniture, go with the stoutest dedicated mortiser that you can, i.e. a floor model. The Jet fits the bill.
It came to pass...
"Curiosity is the ultimate power tool." - Roy Underhill
The road IS the destination.