The board is amazing. I've been using my Arc Board for almost a year now, mostly daily as a commuter. Board is super reliable, almost no problems at all.
Max speed is about 35 km/h which is more than enough for the board this size, I've almost never used full speed. Battery lasts for at least 16 km for me (65 kg) with maximum I've got was 18 km. The breaks are amazing, I am able to stop even on ~15 deg incline. It is very light (~ 4 kg), I am carrying it around with one hand without any problem.