I have a Noveske on a 18" midlength. Runs great. What's nice about the switchblock is that you can reliably go back and forth between suppressed and unsuppressed, or completely off if you want to single shot it. Gas blowback is greatly reduced when shooting suppressed. Just don't lose the key, you won't be able to adjust the block after a few dozen rounds without it.
The JP style adjustable gas blocks work fine too, but if you want to go back and forth, it can get tiresome.
