I install a new radiator cap every time I open the radiator cap. The new cap, OEM-Chrysler, is working. Its more expensive than a dime-store radiator cap. Only time will tell. Price is an issue, as this cap is much more expensive than the junk you could end up with. Sometimes you should just pay the price. On the other hand, I have never had a radiator cap fail.
We had purchased numerous generic radiator caps as this item is so difficult to get in Australia at the Jeep Dealers. Even though postage is quite hefty, the cap is cheaper than actually getting it from a Dealer in Australia.