"I've used several of these in lofts and eaves cupboards to hold bulbs. They are small and easy to fit and a 0.5mm flex can easily fit through the knock out on the side of the holder.
If you want to have something simple in a loft or cupboard these are ideal. If you want something to replace a ceiling rose and which may need loop in wiring support then don't buy these - buy an MK or similar instead."
"These were a bit tricky to fit in my loft as I looped them and just managed to squeeze 1.5mm cable in, but screws are not very strong. Ignore the wiring instructions as they are confusing and incorrect. They instruct you to instal the neutral wire in to the loop earth terminal. Instal as normal with earth at the top terminal and live and neutral in the two connections below. Since fitted they have worked well."
"I usually use crabtree but they were sold out, so I bought a couple of these. The instructions said to wire in with the live fixed and the neutral switched! A little digging round the net, I read that the instructions were changed at a later date, shocking! The terminals are fiddly, does not feel solid at all. Just buy something else."