Has anyone messed with the DD firedragon optics?

I've had a DD firedragon 532nm, the 300 mW version from the GB, for about a week now and I'm quite happy with it as it peaks around 400mW. As everyone who has these knows, the beam is quite fat, ie the divergence is poor. The laser is focusable, but in messing around with it, I've found that it was pretty much well focused to infinity from the factory.

Has anyone tried switching the optics out on these things to get a thinner beam profile?