most efficient lehner

what is the most efficient lehner setup i could use in a rustler with 3s or 4s lipo? i already have a basic 4200 and its great but im building another rustler up and i need another motor and controller. i will buy the mgm controller since it has the lipo LVC so i dont have to deal with an in line LVC like i do with my bk controller. im really interested in the xl series but would they give me better runtimes than the basic series? i would prefer running 3s lipos but if its necessary i will go 4s for efficiency. thanks.

[Serum]

Aim for about 37000 rpm, and you should be fine.
A hot basic can draw more amps than a less hot XL, it depends on the kvrange. Normally the XL has got more torque, but is able to draw the batteries a bit quicker as well.

[RC-Monster Mike]

"most efficient" would be a 19 series(special order). Of the in stock items, I would agree with Serum. For extended run times, the xl will run cooler, so this is what I would recommend. xl3600 or xl3100 for the 3s or 4s Lipo would be a pretty nice setup.

[Serum]

XL 3600 for the 3S and the XL3100 for 4S

It will FLY! pm 4S..

Use Lipoly with a high discharge rate.. (high C)