I just recently traded in my 2006 for a 2011 GT for the sole purpose of having the 5.0. I did look at a 2010 but didn't actually test drive it. I like the sound of 2006 4.6 3v engine allot better than this coyote that's for sure. But yea, it's faster. Make sure you get the 3.73 gears if you can. In my 2006 GT I averaged about 19 mpg. In this 5.0 I get about 17.6. If you plan to change out the stereo, be looking to spend $400 just on the installation kit. That is a big downer in my opinion. I've had my 5.0 for about a month and so far, have had no engine trouble, though It does seem to use a bit of oil. I've used about a qt after 5-6k. Both of the motors in my seats have gone bad tho and that really sucks since you have to replace the entire track for $300 each. 1 week after my purchase, the driver side seat stopped working. I got it fixed under warranty. about 3 thousand miles later and an expired warranty, the passenger side stopped working, too.
Sure it's about 3 grand more expensive, but in my opinion, the 5.0 is worth it. I mean, that's what a mustang is all about, right? The muscle. I can't understand why somebody would buy a muscle car without the muscle. 315 vs 412... more muscle. A mustang is supposed to be a fast car. Think about it, you don't want to lose a straight to a guy driving a Focus. No! You want him to know you've got a stang with a 5.0 V8. People buy mustangs for the power. If you're going to buy a mustang... buy a mustang. A real mustang. Not the watered down version. Get the 5.0 badge and the 412hp.
C is for Cookies. That's good enough for me.