I've brewed three batches using this and getting ready to brew a fourth. So far, I have loved it and find it easy to use/clean and it helps me brew great beer. The only issue I ever encountered was when I got the ER4 code several times during a brew and I had to use the reset button (not easy with a full boil but possible depending on your setup) to clear it up. Turns out that was all my fault and not the M&B. This was during my second batch and I was using a recently purchased second hand Barley Crusher which had been set to a fine grind because the previous owner was a BIAB guy. To make matters worse, I was brewing an IPA so it was a heavy grain bill. Anyway, the extra sediment causes the thermostat to trip so that's something to watch out for. I have since brewed another batch with the correct crush setting and everything went perfectly. In troubleshooting this issue, Bill Moore was extremely helpful and even offered to install a new thermostat that has a +5 degree tolerance over the original part free of charge.
Overall I would say this is a great brew system, especially for the price. One caveat I might add would be that it would be difficult to use for really high gravity beers unless you did a half batch. I'm actually going to try a half batch Barleywine soon. I think my IPA used about 14lbs of grain which is pretty close to the maximum it can handle.