For brazing, heating, and cutting single stage regulators are OK but if you envision using your set to actually weld with 2 stage regulators are much better. They don't vary in output to the torch because of flow rate or remaining tank pressure.
It's nice to buy a set but piecing one together from used or new single items can tailor the setup to your needs. I bought the Victor journeyman set years ago and have since replaced every one of the pieces in it, kinda' making me wonder why I bought the set in the first place.
I do plan to weld with it, not a bumper or any other large project but there have been many times were it would have been very helpful to be able to lay down a few 1" long welds on a small project like repairing/making/modifying tools making brackets household stuff etc.
I had read a little about the 2 stage vs 1 stage in the Hobart forum Junk linked above, 2 stage seams the way to go but a new pair of 2 stage regulators from a known manufacturer cost three to four hundred $, witch is more than most sets (witch seam to come only with single stage regulators)
I have read that many people doing production O/A welding, mainly aircraft and bike builders, like the small easy to handle torches. Especially the small Smith and the Meco midget. The Meco is a dedicated welder only (but does a good job of it) the Smith although larger and less handy has the advantage of also having a cutting attachment. So I was thinking about getting this kit
http://store.cyberweld.com/vereandairco.html
Seen it elsewhere for as low as $318, and gets me the small torch and will weld or cut anything I would need too, problem is the small tanks are useless and would have to be replaced, the small regulators are single stage and would not fit larger tanks so those would have to be replaced the hose is short and I would need to add more welding and heating tips,
In comes Evilbay and here is a start of a set.
Sniped these old style Meco regulators a few minutes ago ~$30 for the pair + shipping
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=320180835882&ssPageName=STRK:MEWA:IT&ih=011
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=320180837317&ssPageName=STRK:MEWN:IT&ih=011
They appear to be beefy US made 2 stage regulators; or at least the pic of the Acetylene regulator that shows the back is, he did not show the back of the 02 regulator but it appears to be of a similar style,
I don't have much faith in EBay regulators if they work on arrival there is no grantee for how long, so I am probably going to pick up another set also, any specific recommendations on regulators for welding?
There are a lot on there most going cheap, of course there are a ton of no name import regulators there, staying way from those, Victor seams to be the hot name on Ebay even the lower end import victors are high as long as they are shiny looking, the older lesser know US made regulators seam to go relatively unnoticed I am trying to pick these out,