David, do you already have acetylene setup or you are looking to augment with non-acetylene fuel? I'm kind of going through a similar pros & cons thing myself so interested to hear your rationale. First off the long term goal is to get a TIG setup specifically for welding (probably your exact machine haha)
But on the torch front, in another post I was asking about acetylene bottles specifically for a brazing/heating torch like this. So the fuel commitment is just acetylene because torch uses ambient air. So not quite as hot as A-O so not suitable for welding. But I figure if I ever went to A-O, it would be a complimentary add-on to get the oxygen bottle & regs in the classic A-O setup.
https://www.riogrande.com/product/smith-silver-smith-acetylene-and-air-torch-kit-without-tank/500105
Then in the propane/air world, this torch seems to get high marks for hobby use; silver soldering, brazing, annealing... but I suspect maybe a bit lower heat than above given same tip, but I'm only guessing there. Use a BBQ style bottle & again no separate oxygen.
https://sievert.se/wp-content/uploads/2017/01/Sievert-Pro-86_ENG.pdf
Then there is the non acetylene 'fuel' + oxygen systems. Maybe I am not digging deep enough or looking at the wrong products but it seems like the oxygen addition (unless its a conventional A-O system) can get either spendy on a volume equivalent or specialized to their setup. So if you commit to a conventional oxygen bottle from a welding supplier, why bother with a fuel other than acetylene?
ps on the A-O front, I know some guys that swear by this torch. Spans the range from jewelry to welding tubing frames for aircraft.
https://www.tinmantech.com/products/welding/meco-torch-accessories/