"As an MCB is part of the circuit protected by the RCD, when you test the RCD by carrying out the test at the end of the circuit at 1/2i, i0 deg' , i180 deg', 5i 0 deg', 5i 180 deg', Ramp, Loop and PFC, you also test the MCB at each of these tests. I have used BG mcb's for several years and have found them completely reliable I have never had a new one fail during testing. I have had a couple of RCD's fail but I always carry spares and Screwfix have always exchanged the faulty RCDs without question. 3 stars for features because there are no "features". These MCB's are the equivalent of other makes but better value."
"I like the BG consumer units, they're good value, nicely built and come with built in spirit level. I have however had a couple of the MCBs fail on me during installation or shortly after so make sure you have spares"
"Have purchased BG items for some time but got 2 of these and both failed testing at x5 In. Have also had two RCD's fail as well. I think its back to MK as its a real pain to have to change them when its all in and you start testing."