I don't think many members here would buy a 6.4L powerstroke. They aren't exactly known as being a super reliable engine or easy to work on. Well, the diehard ford owners will tell you that once you've gotten proficient at ripping off the cab, they're easy to work on. The good news is, if you buy a 6.4L, you'll get very proficient at ripping the cab off relatively quickly it seems. They seem to hold power ok stock though.