For non-diesel automotive use I have been happy with the Dexcool type antifreeze (the orange stuff - learned after a GM dealer, no less, refilled my Grand Am with the green stuff after a head gasket change - shortly thereafter I bought a heater core and a radiator in rapid succession, and another month down the road THEY bought a new cylinder head). Probably not all that important on an earlier Jeep with it's iron engine and no plastic & aluminum cores & such, but having been around a lot of recent GM stuff I got into the habit of just buying orange. When doing a flush & refill I also like to use a little bottle of Bars Leaks, usually the semi-liquid form that comes in the grey bottle. I very recently did my '87 and tried their Goldenseal powder this time. Hard to tell whether either of those products work as a preventative - did it not spring a leak because of the Bars Leaks or because it never was going to anyway? They say manufacturers (which ones?) put their stuff in on the initial fill, I dunno. It's cheap and it can't hurt.
But like the others upthread say make sure everything's good and clean and the radiator and hoses are in good shape. Hoses seem to last a lot longer than they used to. I think my '87 has it's original hoses (but a brand new radiator) at 200,000 MI, and I KNOW 100% of the cooling system on my bought new '83 S-10 is original, and it all looks fine. If all else is good, heat-cool cycles will get to any radiator eventually, so I'm probably just lucky with that S-10.