I usually try to go factory for late model parts but sometimes the price difference is dumb. I put a thermostat in my wife's 15 Grand Cherokee with the 3.6 this weekend. Dealer was like $70 and duralast was like $20 haha. I did go with factory coolant. Nice O-ring gasket and a bleeder built into the housing made it a quick and easy job. I only had to use a very small amount of that $28 coolant jug I bought haha.