SpeakerCraft, Niles, Klipsch, and Boston. I have had the Niles and speakercraft's in a prior home, but now use Triad for some side surrounds in the ceiling. I actually found the Klipsch in-ceiling/inwalls to be not too bad. The extra hot highs made it sound better at low background music levels, than say the Boston's did.
Speakercraft is kind of a specialty mfg, but they produce some good inwalls.