What I went for: Azub T-Tris rigid tadpole 26" rear 20" front wheels, Rolhoff 14 speed hub, Steps E6100 with 630Wh battery. 90mm drum brakes front coupled disc and parking brake rear.
It rides really well out on the road but in tight spaces the handling and turning circle is nowhere near as good as my Kett.
padded seat is really comfy compared to the old kett mesh seat.
in terms of range I have only ridden it in 'eco' mode on. have done a couple of 90-100km rides with 500-600m climbing (some of it 15-18%) and returned home with 50km in the battery. average speed has increased to 20km/h from a long-term average of 16kmh, so I think the advertised range of 'up to 200km' is probably right as long as it is pancake flat and slow. I think going for the bigger battery has paid off but when I do another long international tour i will probably consider a second battery
Gear change somewhere in the middle , between 6 and 7(?) is a bit clunky but otherwise it is smooth and means i can keep going up hills. on the flat i seem to be routinely riding gear 12 without much assist. in the hills i am still getting used to more gears and learning where to be but enjoying overtaking the two-wheel uprights in lycra!
its hard to know for sure but think the 26" rear is giving be more bangs for my buck. when i switch off assist my 'one-leg-drive' is much faster than the 20" kett.
hope this info is of help/interest.
Skel
BTW my Heinzmann powered Kett is going on Ebay soon to help pay for a clip-on to turn my wheelchair into a motor-trike, so beware on the pavements of York
