I had a M18 Pro and used the Lehner - 1015-12T (6667 kv) with a Mamba25 ESC with Thunder Power 2000mAh 2S and TP 1320mAh 3S lipo packs.

I have since destroyed the M18, but I got myself a M18T and transfered the electronics into this buggy.

My runtime geared for about 35mph is easily 25 - 30 minutes. I also love that the LMT motor is just the perfect size and has a 1/8" (3.2mm) shaft so you can use the lightened Robinson Racing 48p pinions.

Congrats on the xray - they are so well built!

Also for a servo - I went with the #389170 XRAY XMS01MG Micro Servo – Metal Gear for the M18 Pro and I am using that in the M18T as well. I think it does a fine job and it's a perfect fit for the car.

ya as far as m18pro goes i woulnd't do more than 2 cell lipo regardless what motor you put in it. tires are going to cost you 10 a side and they go out super quick. especially with lipo/brushless on high traction surface. just my 2 cents