Regarding Kiwi's point -
I know what you mean about the Jungheinrich control cards, it was a problem here about two years ago when they first set up the 24 and 48v with AC power. However the reliability now they have gone to making thier own cards is much better, plus they are now much cheaper...
Regarding John's point -
The idea that a 3 wheeler can ever be as stable as a 4 wheeler is interesting. The german equipment is now coming complete with systems like 'curve control' to reduce speed dependent on steering direction but I don't think on counterbalances you will ever beat wheels at the corners for stability. 4 Wheel a bit of a compromise on turning circle sometimes, this is where 3 wheel is certainly best.