well it all comes down to racing style and opinion....
i use my MR02 for racing... but thats because i like the way they drive and feel.... where as my ma010 is slightly different which is ehy i only use it for drifting... however it is AWD and with some tuning can be a good car but with miniZs you pay more but you get for what you pay.....
in my opinion id start with an MR02.. and see how you get on... then move on to something else
just my 2Cents!
Michael