You might consider the JR Propo Z3550 servo. I have been using them for 1/12 scale for a few years now. They are extremely fast and very very reliable. I have never had one go bad, and I race alot of 1/12. It looks to be alot cheaper then the KO you were looking at KTHobbies. Here is a link you can get it direct from Horizon Hobby for like $63 bucks...

JR Z3550 link