Re: CZ 453 Varmit
The other difference between the Brooks kit and a Rifle Basix is that you can order the Rifle Basix and actually get it. I ordered two trigger kits from Brooks about two and a half months ago and have not received a thing. Nor has he bothered to reply to any inquiries. He sure as hell took my money, though.
Some people report receiving orders immediately, but an awful lot of others seem to end up ripped off like I was. Rimfire Technologies, by contrast, has been a pleasure to deal with.