http://www.lehner-motoren.com/
The LK versions have the cooling fan in the front of the can- not really needed for ground vehicles due to sucking in dust.
The HiAmp versions have a single wind of wire apparently, meaning they draw more current but produce greater power, or some troddle like that- only much use a giant plane or boat with good airflow or water cooling.
In general though, the lehners are 2 pole motors, meaning they spool up faster and are good for high rpm setups, but for ground vehicles over a certain weight range the 4 poles Neus and similar motors ( castleneu, medusa ) are better; these are slightly slower to spool up but produce greater torque/ are better at pushing things like truggies and MTs (less likely to overheat).
Given the prices and relavite performance, I'd say stick with ccneus as they are everybit as good as a true neu motor and alot cheaper; I paid £120 including postage for my new 1518 motor, thnough add on £30 for import fees and taxes.
Price may not be much of an issue, but I see no sense in paying more than double for a motor that isnt much or any better..