I have the Tiger and my brother has the Pershing. Both very nice. They are not truly proportional but rather electronically "stepped". You can just about creep along nice and slow if you've got good fingers on the sticks. The quality is very nice for the money. They don't really stand up to comparison with the Tamiya offerings but for a fraction of the cost the HL's can't be beat. In the US the best place to orderfrom is MATO Toys as they inspect and test each one before shipping. QC used to be an issue with HL last year but I'm not sure that's improved. The Airsoft mechanism looses a bit of zip over time but I sort of lost interest in the gun after a while so no matter. I also removed the smoke system as I never used it. I'll install it in a boat or something.
Regards,
Mike