Hi Roger. I just recently joined myself. One of the bikes I tested before buying the one I did was the Magnum Metro. It was really a toss up for me between the bike I got and the Magnum Metro. I liked it a lot when I test rode it.
My wife's bike has a mid-drive (torque sensor) and my bike is a rear-hub with a cadence sensor. I've ridden both our bikes, so I can give you my take on how they feel different. The mid-drive/torque sensor feels more natural. It feels like riding a regular bike, but now you have bionic legs that makes it easier. The level of assist sets how much help it gives. The amount of power added by the motor is based on how hard you are pedaling.
The rear-hub/cadence sensor setup is more on and off. On my bike with the cadence sensor, the motor turns the rear wheel at a certain speed based on the assist level. At 1, this is 6 miles per hour, at 2, it is around 10 mph, and so on. Now, my pedaling can make the wheel go faster, but I can't go any slower. The cadence sensor has no way of telling how hard I'm pedaling. It just knows the pedals have started turning and when that happens it turns the motor on.
Both systems have pluses and minus. The mid-drive/torque feels more natural, but is also more complex and expensive. Most rear-hub cadence sensor systems allow you to use a throttle if you want, and are less expensive. Both systems are fun to ride and get the job done