Once you get used to Surefire, there aren't too many other brands that will meet your expectations. But there are still a few options -
One that applies to your current Surefires and Mags would be drop-ins from Malkoff Devices:
http://www.malkoffdevices.com/ . Anything from 200 to 700 lumens in basic and very solid drop-in form can be found there.
As for manufacturers, you might take a look at NovaTac (
http://www.novatac.com/) and JetBeam (
http://www.bugoutgearusa.com/jefl.html), both are common also-carry favorites with many Surefire owners.