4 speed od or 5 speed

I had a Dakota with a 5-speed that I put over 100K miles on it.
The trans is not that bad, it is like about any other 5-speed truck / Jeep transmission.
Plus it is already set up for a hydraulic clutch.
The easiest thing to do is go out on a car lot and test drive a vehicle like the one the trans come out of, see if you like the gear spread.
If you cannot find a Dakota to test drive, alot of jeep wranglers from about 1999 to 2006 have about the same ratios, plenty of them sitting on car lots.
Only you can decide if you like the gear ratios.