Great Review Ypedal, a great looking bike too.
As I understand it, after Tidalforce went Belly-Up, some engineers went on to start E+, and engineers went to start Ultramotor.
E+ licensed the great tidalforce technology from Matra, which puts the battery mass in the front wheel, balancing the mass of the rear hub motor perfectly, while establishing a very low COG by putting the mass around the axles. BTW, I'd recommend adding the E+ 1000w bikes on your list of commercial bikes worth tring, the balance and production quality are great even though the price is not. I picked one up earlier this year at a major discount, it is also waterproof, and with pedalling you can break 30mph.
However, Ultramotor was not constrained by the existing technology and started with a fresh design, and IMHO did it right. They maintained the tidalforce commitment to front/rear balance and low COG with the small wheels and in-frame battery. The smaller wheels helped boost torque without increasing watts. However, they added full suspension, disk brakes, and lithium chemistry. They also hit a better price point better than E+'s $3,500, although IMO it will take a bike of this quality coming in at @$1,800 for the ebike market to explode, and the company doing it will become the 'kleenex' of ebikes.
When I was negotiating with E+ to buy a few hundred motor/battery kits to retrofit to my TF frames, I tried to counsel them on their price point, not to mention brakes and chemistry. They didn't get the message, which is too bad, when gas was high and the economy hadn't tanked they had a chance to establish their brand as the definition of ebike, at least to the ready-built market.
Oh, until your review, I didn't clue in that A2B uses the Alex DX-32's - I used them in 26" on my BMC build and they are my new standard, they totally rock Hookworms.
I also noticed that the kickstand is identical to the "Durable Double Kickstands" I've been selling for frames with 26" wheels. The proportions look the same, I wonder if is the same stand but the mounting point is higher on the A2B allowing for 20" wheels: