I have 2 for sale, a 97 12 valve, and a 98 24 valve. I bought the 97 to replace the 98, and haven't had any luck selling the 98. The 97 is a 5 speed, the 98 an automatic. Come test drive them and take which ever one you like home.
Honestly, I like the 24 valve engine better myself, but the 12 valve is eaiser to increase performance. I don't think you'll go wrong with either truck, as long as it's been taken care of.