I have some 0.30 but I haven't' used it, I bought it by mistake. It's flux core, my tips are 0.35, so I just use the 0.35 flux core wire. I do have some thin, sheet metal to repair on the outside of the car and I knew that the time to add the gas bottle, was when I start doing the sheet metal on the bodywork.
I'm sure that once I use gas, I'll be just like the rest of you guys- Probably won't weld without it. For now, I have lots of big bulky stuff to do with this cage and plates, so I'll be sure to comment on after I start the bodywork. Cool thread, lots of smart guys on this board.