Anyone had any experience with this kind of thing?

LP stopbar Trem on Stewmac

I'm looking to try something like this (probably this specifically, unless there are any others people know of which don't cost a fortune!) on an Epi LP Custom, and possibly also a Gibson LP Classic Antique if it works out fine on the Custom.

Anyone know how reliable these kinds of replacement bridge trems are? It says it only manages about a half-step in either direction, which is all I'd be doing anyway (I don't need to be able to do divebombs or anything severe, so that's not an issue). Anyone know how well they stay in tune, etc?
I'm aware, but I'm reluctent to get a Bigsby because quite simply, I think they spoil the look of the guitar hugely, especially in the case of my Epi which has had a custom paint job.