MRX3
The mrx3 is an excellent car out of the box,very responsive to setup changes while being very forgiving of rookie setup mistakes. I would never count on a model change being geared toward the ability to upgrade prior models as that would place many restrictions on the designer.The purpose of any new car should be to provide a better car,not just promote parts and kit sales.Mugen product support might not be the best but you can count on anywhere you run the car someone will be able to give you setup advise.MRX4 rumors are flying everywhere however for a rookie breaking in with a brand new model(new to everyone)is not always the best plan,stay with a model that people have had a lot of experience with.