Most frames are made in just a couple different factories in China or Taiwan, the frame geometry is more important than the Brand.
I built up a Aluminum Kona Jake the Snake with a Carbon fork and put 1000 miles on it in the last year. I started at about 270# and am about 245 now. Your wheelset needs to be strong or else they're going to go out of true often. Probably a set of Tandem or Touring wheels would suffice. You could build up a Surly LHT or Crosscheck and not have to worry about any frame "issues" at 300#...