I love my FX, I've had it fully submerged in water, I've jumped it, I've put 3,000+ miles on it and ride it almost every day, I also have a short commute to work (there and back is maybe a quarter charge).
the 13FX 5.7 has PLENTY of power (that second battery adds a lot of "top end" power, I've ridden with just one when there were some battery issues earlier this year).
there's a couple of things to watch out for that I've experienced, listen for a "clicking" while riding, it's an easy fix and well known, but if you have it you need it treated. the rear brakes will probably squeel, mine still do it a little now, but I never tried to correct it.
if you're not carful with the throttle the front wheel will lift off the ground all the way to about 35-40 MPH, the bike is VERY light for it's power so be aware of that.
other than that, I think you'll enjoy it a lot!