Thank you all for your thoughts and suggestions. One of the reasons I'm leaning towards the mid-drive is the aluminum frame is a concern for a hub mounted drive. I like the idea of the weight concentrated low and in the center of the bike. I've only had the opportunity to ride 3 types of Ebikes, 2 were different models of Pedego with rear hub drive and the battery mounted over the rear tire. I found them very fun but not very "bikey" more like a two wheeled motorized scooter. Then I tried an Erad mid-drive conversion on a fat tire mountain bike. This felt much more familiar and gave one the feeling of really riding a bike with a seamless assist.
My biggest concern here is the road bike aspect and the aluminum frame. Most of the ebike I've seen place a premium on upright non aggressive riding poster with large soft tires. As road bike riders we have placed a premium on light weight & low rolling resistance.
I would very much like to hear from anyone with experience on a road bike conversion.
My conversion was a road bike (touring bike with drop bars) conversion. I run 28mm tires on 700c rims. No suspension steel road fork. Most of the weight of this system is the battery. As you can see, it is quite low and centered.
My bike rides exactly like a bike. I did not install the throttle, so it is pedal assist only. Your BionX dealer can dial in the settings on the console/controller to get the exact feel that you are after for each of the 4 levels of assist. The first 3 levels on my bike are "seamless." Level 4... when you press on the pedal, you feel a "smooth burst" of assist initially... then it smoothly continues on up to cruising speed. I had the dealer configure it that way.