Chrysler Repair: 06 Town & Country Limited 3.8L, ngk iridium plugs, champion plugs

Question
I am considering installing NGK iridium plugs in my van due to the supposedly better fuel mileage and performance they offer. What is your opinion on these plugs? Are they really better than the OEM Champion plugs? I have heard of situations where these plugs are actually detrimental if you do not have a high performance engine. Your thoughts please.
Thanks for your time.

Answer
IMHO, the actual fuel mileage increase is never enough to offset the cost of plugs. The engine and fuel systems are designed to work with Champion plugs. We have had a few cases where the plugs have been replaced other brands or types and the customers have experienced driveability concerns.