Paul
I looked into options for a couple of months.
Went with this outfit.
I liked the straight forward presentation. A bit more $ than some other sources, but I like to know there is a real person to talk to if I need something. So far, it's seemless. No Issues at all. (And Nicely packaged and shipped to boot ;-)
BBSHD mid motor with a big 48 V battery pack. The battery was about as costly as the motor kit. And so far, it appears I didn't need as much capacity. My butt gets sore before the battery shows discharge ;-)
It took me maybe 2 hours to "convert" my GT Richter 8. Steel frame . I did purchase the bottom bracket tools, so that was all a breeze. fiddling with grips, shifters levers and wires takes the lions share of the task.
Why? I'm getting too lazy to pedal our hills, and I don't consider walking a bike much fun.
Why a mid drive? More like a motor bike, It just makes sense to me.
The Bafong kits are well proven, reliable and parts are readily available if needed. I had considered a more basic (read higher power) motor/controller build, but thought I should see how I liked the e-bike before putting in all that time to fab brackets etc. Plus, the DIY path ALWAYS COSTS about double what you think it will. BTDT too many times ;-) The "kit" is the Kit, Only one charge on my cc.
I want to spend the $15 for a controller to PC interface cable so I can reprogram the controller. I didn't want to mess with settings until I had some experience. Since I can't leave things like that alone, I purposely didn't get the cable with the kit.
Also I'm looking at slightly larger tires for softer ride and flotation for our muddy forest conditions.
I'm running hybrid road/knob side tread now, they spin like crazy when it gets slippery.
Take a look at the BBSHD you might like to do something similar.