I absolutely hate their rails. The tension is consistently good, but when reinserting sockets, the holder slides way too easily in the rail. This causes the socket to not be easily inserted with one hand. You almost always have to re-center the holder between the adjacent sockets first and hope it doesn’t slide before the socket clips in. If it does slide, the holder will not be centered and the socket not insert. This is very frustrating when you use them often.
If you like rails that are way too long for the sockets you have, then maybe it isn’t a big deal because you can leave a lot of space between each socket. I suppose it wouldn't bother folks who don't use their sockets much either.