The UCC305 is one of the best values in the marketplace. They are bulletproof. Has one $100 board in it and one contactor that seldom needs replacing. Weighs 965# and has a nice form factor - flat on top so fits nicely in shop. Run some 6/3 cable to it from your breaker box. Came out in about 1970, Linde's first solid state tig welder that they built themselves. Being solid state, it will accept the new fingertip controls that fit into torch handle in case foot control is not convenient for your application. I remember being at the Florence, SC plant in 1973 where Linde built the 305 and they gave us a sample of the insulation material used in the coils and challenged anyone to tear it. Teeth, knives, tools - nothing touched it. They use anodized aluminum straps that have leads of copper thermal-compression bonded, I believe is the term they used, to them. At any rate, I have seen one transformer failure in thirty years, and it looked like something got into transformer from outside. This is one tough little guy. Had one of these in my garage for a decade. Never opend the case.
As for gmaw, the story is same as for any tig. The 305 will do the same good or bad as any other single phase tig. The main drawback is that you need the expensive arc voltage wire feeder to get halfway decent results, but on that day someone leaves the hi freq on, there goes the board in the feeder, and that one is not $100. Bad day in the shop. Weldersales