Hard top for 90 YJ
The only real con I can see to ABS, is a few more connectors and some other pieces to breaK or get messed up. My philosophy has always been, the more complicated the machine, the more chance of it breaking.
An intigrated ABS and traction control is probably, the direction of traction future. I´ve seen some vehicles with rear wheel electronic traction control, I was impressed. Have a truck with rear wheel ABS, works good, helping keep it straight, going down a slippery slope.
Most systems, I´ve seen, require some kind of reprograming, when the tire size is changed.