There have been a few products that I have brought home to “demo” and never brought back to the bike shop. I brought home a demo Litespeed Tuscany one year and loved it so much I kept it. I’m afraid the Bionx is going to be a similar situation.
I frequently tow a Burley piccalo with a Burley D’lite attached to it. The added weight of the two trailers plus kids ranges from 125-150lbs. The bionx electric assist makes it easy to pull this load. In fact, most of the time I dial the bionx down a little because I do not want to bike more than 15mph with such a long and heavy setup. I find I use the bionx control panel like a third shift lever and dial up the assist on uphills or sections of road that I want to get through quickly. I also really like the regenerative brake feature. It is amazing how much the electric brake will slow you down.
On the commuting side of things I find I leave the road bike at home for my 10 mile commutes. I can pedal almost as fast with the bionxed Xtracycle and I can carry all kinds of stuff to work that in the past would have tempted me to drive a car. I can say that this setup has gotten me out of my car and on my bike many times this past month.
After 350 miles of biking, which has included snow and rain, I have only had one problem. I wanted to set up my bike with disk brakes. The hub I received did not have threads to accept a disk. I mentioned this to our Bionx sales rep and he insisted on replacing the entire wheel with a new one. My only criticism thus far is rather trivial. The button to toggle between time, distance, and odometer displays is rather small and requires a finger nail to push it.
So far I am getting the range I expected. Obviously, towing the two trailers cuts into the range quite a bit. Even without the trailers my unloaded Xtracycle weighs about 70lbs including the 14lbs of motor and battery. Without the two trailers attached I am coming close to getting the advertised range. When I commute I mostly ride on either the level 3 or 4 boost. I have not tested level 1 or 2.
When Bionx catches up on the demand I am going to let someone else at the shop test out this system and I am going to try the PL-350. One way or the other, I will have a Bionx on my Xtracycle for a while.

It’s almost a year later. Anything new to report on the ride? Battery life?
Did you try the PL-350?
I just ordered the 350 for my Xtracycle bike. Looking forward to it.