If you don't mind used, there's also Yashica-Mat, which is all I've used. No issues with mine, which has seen a lot of miles. The viewing glass is a little dim, but I don't know if that's particular to the Yashica or not.
There is also the Maymiya C330. It even has interchangable lenses. If you have the money, I'd go with a Rollieflex or the Mamiya.
Rolleiflex, Rolleicord, Mamiya, Yashicamat, or Zeiss is what you want to look for in a TLR. You will be able to find them as cheap or cheaper than the Seagull, and they are all better quality. Seagulls aren't all that bad, just way over priced. I would never pay more than $50 for a Seagull.
When looking at the lenses you are going to run into 3 main types: 3 element (anastigmat), 4 element (tessar or xenar), and 5 element (planar and xenotar). The names in parenthesis are the names given by Zeiss and Schneider. The more elements the higher quality, although most of the quality increase would be noticed when using the lens at the wide open apertures and at the edges of the photo. Stopped down to f/8 through f/16 they all do a pretty good job. The Planar on my Rollei is as excellent as any MF lens I've ever used. The anastigmat and tessar lenses I've tried are pretty good too.