I'm running an MTC ProCal. It has its good and bad points.
The pump. My MTC reactor uses an Iwaki 20RLT, for recirculation. The reactor doesn't require a feed pump, as the intake is tee'd from the intake of the pump. Running it 7x24 isn't saving me any money, but the use of a pressure pump as opposed to a powerhead really pushes the water through the media, so clogging up as the media dissolves isn't as big an issue as it is with other reactors.
This reactor is as close to "set and forget" as I've ever used, and I've used a bunch of commercially available reactors, like LifeReef and Precision Marine. It never gets air or CO2 locked and the drip rate never needs adjusting once it's set. It's not easily cleaned, but luckily, it only needs to be cleaned once or twice a year.
That's my .02