Lincoln, Miller and Thermal Arc all make 180 amp welders in that price range, and any one of the three would be fine. Between them, it is like having a chevy/ford debate, it's all about personal preference. I don't know if ESAB makes a tig in that range, but they are pretty good too--I have an ESAB plasma cutter, and it rules.
I run a Thermal Arc 185 tig setup and I fucking love it. I got it for $1600 on ebay a while ago.
what is the best in the 1500.00 - 1800.00 dollar range