A lot of racers use these :
http://www.hobbyking.com/hobbyking/s...6_models_.html
121mm lipo is to long for the chassis !!
If you already have a transmitter and receiver then i would personally go for the kit version. I`ve seen the RTRs front dog-bones causing problems with binding etc , so they will need replacing for CVDs quite soon ( £24 for the pair !! ) You won`t be disappointed either way. Very strong durable buggy. In more than 18 months of carpet racing i have spend very little on replacement parts
I did replace the wing with a Carisma GTB wing because the LC wing is very fragile!!