Our previous home had Goodman AC. It was 10 years old when we had a pre-summer service on it. The old AC guy (probably in his mid-late 60s) said Goodman was a really good unit. He said he's been in the business 40 years and seen them all. That made me feel better about it since I'd never heard of Goodman before.

He said they manufacture units for other brands, IIRC. 

This is in Phoenix