[vin63]

It sounds like you're on the right track. I would look to the smaller bottle, too, for mobility purposes, etc. I use the smaller bottle size for my MIG welder because I do a lot of off-site work and muscling around the larger bottles would get old fast. I do have a large tank for my TIG welder, but that's because it never leaves my shop and I do 10x more welding with that machine. Check also the gas mixture the suppliers are offering. I use an 85 argon/15 CO2 MIG mix that my supplier (Praxair) offers - I use Praxair because I had an account with them many years ago when I lived in NorCal, and it was convenient when I moved to SoCal...but, I also work with AirGas for other things that Praxair does not carry, etc.