Depends on what you use the car for.
If just cruising around, visit local ice cream shop with your kids or significant other. Leave it stock. Get a shift kit a decent trans cooler (actually any trans cooler is better than what the factory included) and call it a day.
If drag racing is high priority, sure, put the other converter in. You can launch harder (not needed for cruising).
If autocrossing or track racing, I don't have experience here but I would think that the stall could produce a not optimal performance (essentially limit low RPM usage).
I have a stock AOD in my 90, with a stock torque converter and a Lentech VB (fixes the shift pattern issue too). I have a mild set up as well, probably 330-350hp at the crank (never tested but 1/4 mile on the street MPH would put it around there). I launch from idle with a short tire chirp and chirp 2nd and 3rd with 5500 rpm shifts. Drives off at idle nice while cruising and shifts smooth. I like it.