After some (minimal) research I found out that Teenage Mutant Hero Turtles has its own RPG book:
Teenage Mutant Ninja Turtles & Other Strangeness.
Some parts of the system above appear good, such as character creation allowing for a variety of mutations, and other bits, but by and large I'm not keen on the mechanics. It's based on the Megaversal system, which looks a bit odd.
Were there alternative systems based on this franchise? Or even re-flavourings of other systems?
The system above (Megaversal1) seems to be suited more towards the original animated series(1987-1996) which is heavy in slapstick comedy, and as a whole is less serious. The latest series (2003-2009) has a much darker feel to it (evidenced by this line of artwork), is more serious and sticks to the Mirage comic line, whilst preserving a Rule of Cool.
I'm looking for a system that will let me emulate the TMNT style to my hearts content, as well as having a setting and character very similar to the 2003 cartoon, this would mean it having (roughly in this order):