My '05 4.4 has had a cracked coolant tank replaced under warranty.. That's it. Runs like the beast it was supposed to be. Most folks on this forum are typically trying to fix or mod something so there tends to be a lot of talk about what broke or isn't working correctly. I own a motorcycle as well and same thing happens on our Yamaha forum. Not to many people log in and post "just wanted to let everyone know I got to work today again for the 800th time with no issues". It's typically the one time event that we can't fix right away thay gets posted... As it should. This is a community of owners trying primarily to help each other out. Alright enough soap boxing. Love my X.. Buy the 4.6 if it passes your due diligence checks. You will be a happy X owner like 99% of the rest of us!