I race against 10th scale Hatzenbachs or a few years now.
I was also handed the transmitter of one every once in a while.
The car has massive rear traction. They have used every trick in the book to bring steering into the car (and succeeded).
However, the car's handling is on a par with a good stock Associated L2 (and my X10 for that matter).
The guy behind Hatzenbach is working on a refined version of the car that is ready for Lipo batteries.
See here:
http://www.moosi-masters.de/forum/viewtopic.php?t=1338
He's just about ready, just waiting for some parts to come in.