There's a number of them that are very high quality and low maintenance.
VAC, Atma-Sphere, BAT, Lamm, Music Reference, Herron, VTL, Rogue all qualify IMHO. Audio Research is one of the biggest brands, but while they certainly have a large number of fans, I have heard plenty of stories and had one personal experience where they are a step down in reliability (and repair cost) vs. those mentioned above.
The Air Tight I once owned was also trouble free, but my read is that there aren't too many sold so it's hard to get a meaningful sample. Cheers,
Spencer