my parents have had/do have the follwing minvans:
89 grand caravan- 4 cyl, slow as hell, TERRIBLE engine trouble(it had a mitsubishi engine..nuff said)
93 grand caravan-v6, 160HP, not that slow, good engine, on its 3rd tranny, it is trying to be sold right now
98 pontiac montana- v6 170 HP, slower than the 93, loaded, every option in the book, but its handling is TERRIBLE and the seats are so low that your legs fall asleep while siitting there...no homo
99 grand dodge caravan Sport LE Limited v6 225HP. This thing OWNS, it has a special engine and suspension, with 25 HP more than the normal sports, a tight sport suspension with 17" rims and michilan low pro's stock. I have taken this thing into a 90-degree turn at 50 MPH, NO PROBLEM! Its fast as balls, I can nearly burn my friends 300zx NA...
The tranny is solid, and interior refinement is Top Notch, the infinity system is kick ass, with 8 speakers. Get a 97 or newer grand caravan, they are the best.
EDIT: You CANNOT get this 225 horse engine in any caravan, it was a special one that was sent in the dealer show vehicle, we bought it off the floor...