This is a good executive summary
The double cab with 6.5’ bed is great unless you have frequent tall passengers in the back.
The 4.6 is what replaces the 4.7 around 2010 I think, the 4.6 is same as 5.7, just shorter stoke.
The early 5.7 and 4.6 did have issues with oil leaks ( cam tower and...
Shark bite is easiest quick fix.
If the copper pipe was manufactured in the last 20 years, you will have many more pin hole leaks unfortunately due to poor quality copper, long term best solution would to install PEX, in sectuons