Like any old ride, if you get one that has been abused, it will be junk. If you get one that has been well taken care of, it will likely be a great truck.

I've had a few different Dakotas. The 90 V6, TBI, 5 speed, with a 3:55 limited slip was a fun truck (and was a grate donor for hot rod chassis). Not a race car by any means, but it is fun. I blew up the V6 at around 165K.
The 91, V6, TBI, auto was a great work truck, until a patch of ice did it in. That motor went into the 90 chassis. It got 21.8 mpg on a recent 3402 mile trip.
The 93 Magnum V6, auto, 4x4, currently has around 160K miles. It gets 13 mpg in town, and around 17 on the highway. The 93 spent a lot of its time over the past 4 years just sitting (only driven about 3,000-4,000 miles per year), and as you can imagine, its getting pretty rough. I will replace it with another Dakota, maybe I look for a V8 this time, but the V6s are a lot easier to find. At least the early Dakota were great trucks, some of the newer ones seem to have issues. Gene