I'm just guessing here but you might need to get new hubs to run 0 offset. As far as St. Servos everybody loves Hitec 79xx series but they can be steep but worth it with the warranty. No sense in wasting money on a servo that don't last long. Some people swear by the Ace's (1015 and 1313) I've seen mixed results and heard mixed reviews. A-main just started carrying the Savox brand, these I hear mixed reviews on too but haven't seen in person. Get one with at least 250 oz. of torque for truggy IMO, and a transit speed under .2 is nice as well. Also, metal gears. Oh, and Hobbico and Tower sell a relabeled Hitec 5955 with metal gears and good torque and speed the hobbico is the CS-170, the tower is TS-170 i think. They are strong and fast and a little cheaper but don't have the warranty. I run the hobbico one personally in my truggy and it's worked fine for me. Best bet is to go to search on here and look for a thread called "Good Servo's?" It was started by me when I was doing the research for myself, a lot of good info in that thread. Hope that helps I don't run the Jammin but feel free to PM me with any newbie questions as I have learned my lesson's so far and will help you learn a little easier if you need me.