It won't be too noticeable, but I would say either get the Feigao 380 6s/7s, or the Lehner 5300. Don't go with the Feigao 540 6s. The 380 6s is faster than the 540 6s. The 380's kv is about 500RPM/volt faster, and is rated to pull about 40amps less.

Put it this way: It seems like my car weighs 15 lb when I drive the 540 6s. I've tried 15-23 tooth pinion gears in my xxx4 with 7 gp3300 cells. I've found that a 19 tooth yields the best overall performance and the coolest temperatures. In order to really get this motor's full potential, you would first need HUGE batteries. Three 7 cell gp packs in parallel would do the trick since max efficiency at 8.4 volts for this motor occurs at 130 amps. Then all you need would be a 30+ tooth pinion gear and you would be going 70-80 mph with 900 watts of power! Unfortunately, that type of power is impractical for rc. .

I run a Mtroniks branded 6s in my trucks, and have tried it in my TC3. It works OK in the TC3, but my Feiago 9s will get around a smaller track a lot faster, and have better runtime. I'm going to get a Feiago 380 6s very soon for my touring car.

The 6s is good in heavy 1:10 cars though, I use it in a brushless RC10GT, T3 and T2. On 7 cells it rips in those cars, but it isn't suitable for a touring car really. It would work well (if you use good cells) but it wouldn't be the best value for money.