Espin chosen over the R1U and some others for it's low cost. Good bones = wheel size, motor, battery (in this case the fact it's concealed and inserted from the top, and it's about the right size I was looking for). KT controller and display are less than 100. but there will be some wire splicing necessary. It's NOT plug and play. For somebody used to/OK with DIY working on cars/low voltage wiring it shouldn't be too difficult. I did change the handlebars and riser for a sedate, upright, easy to ride, posture that's easy on my wrists. Stock shifter that didn't tell me what gear I was in worked good, but was a surprise. That was replaced with a shifter that did show me what gear I was in, along with a matching derailleur. Seat replaced, suspension post installed, stock tires were replaced with my favorite 27.5 x 2.4" Schwalbe Super Moto-X for their ride and minimal rolling resistance. Maybe some other stuff as well. Point being, I've been riding e-bikes for a while, and I'm spoiled rotten when it comes to some of this. I'm an accomplished DIY'er as I enjoy working with my hands, and I have the time to screw with this kind of stuff. My bikes reflect this....
R1U 700 features an adjustable controller, which is pretty unique in it's price class. If I made up my mind to just deal with whatever I could get, that would be the minimum.
We put a minimum of about 50 miles on our bikes in an "as received" state before anything is changed (other than maybe the seat, changing that is pretty much a given). The Espin controller is adjustable to a certain extent, and had it not been for that extra 10 feet BS, I might have been able to get used to it/live with it. It was unique in that it featured an automatic PAS shifter. It would let you start out in PAS 1, and as you approached the max PAS 1 speed, it would shift to PAS 2, then PAS 3 depending on your speed. Unique feature! Just misguided. They would have been MUCH MUCH further ahead using that energy by getting the motor to shut down right when you stop pedaling....
I like the idea of riding whatever you get for a bit to see what's going on and get used to it for a while. Give it a fair chance! At that point, ANYTHING is fair game! Make the bike YOURS! -Al