Not great and not bad , there is never any forethought when they design these things for how wiring is going to travel ,the hardboard backing is a complete waste of time ,my advice is just don't put it in as you'll send an age cutting it about to how you actually need it . The doors on the front even at the maximum adjustment are still proud of the top and they stick out at the sides ,not worthy of its price tag , also I could swear I ordered it with the lighting pack yet it arrived with none ! 

For the price it would be nice if it came with longer fittings for a modern house which is block and dot and dab plasterboard , if not deep enough it would simply fall out the wall .