Are they any good? Would one be worth $200 more than a magic chef? Is the beverage factory a repudable dealer?
Yes, the Beverage Factory is a reputable dealer. I have had several transactions with them and they have always been good.
Yes, though I don't own one, I have heard they are OK. I don't think they are metric, so that is good. You will still want an external temperature controller.
FWIW, I also installed a tower blower so that the beer in the lines in the tower don't warm up as much resulting in a 1st glass of foam. I also got a cheap fishing temperature gauge, the sensor from it is sitting in a beer can filled with distilled water inside the kegerator. The reason for that is liquid temperature is what you are concerned with, not air temperature. But the most important item is the temp. controller.
If you think you'll want a double faucet in the future then the Magic Chef becomes more attractive because you'll replace the whole tower so the metric part doesn't matter then.
In your shopping also look for a Danby. They are probably the most common kegerator out there. They have the same issues with needing an external controller though. And they are more difficult to install the controller... but they can be had for less than the Summit.