I am currently using a MB36 torch with my 350amp Sip welder, while a bit unwieldy it works fine as almost all of my work is on 6mm+ stock. I have got to do a job on some lighter material (20mm 2mm wall box and I think a smaller torch might make life easier. The question is what to buy - Can I get away with just buying a MB15 or should I bite the bullet and get both MB15 and MB25 torches.