I was told the 3v was a pretty reliable engine. Have a friend that has one with over 2k on his with no issues.But it's a 3 valve Ford. The 4.6 can have the same issues as the 5.4.
They have problems with them blowing out spark plugs. And problems with the VVT. The spark plug design changed from the earlier years but they still shouldn't be trusted.I was told the 3v was a pretty reliable engine. Have a friend that has one with over 2k on his with no issues.