Going from a Smith's Little Torch to a larger but cooler flame will take some practice, but is possible. The concentrated heat of a small Oxygen/Acetylene torch can be hard to control, but when you get used to it, nothing else seems to have the horsepower and finesse that it does. When I tried one many years ago, I found that a Smith's gave such a concentrated flame that I'd blow right past the melting point of the silver and soon have it bubbling and weakening the joint. I've since learned to control it, but find it's not my preferred torch.
I've used MAPP gas (or the current equivalent MAP/PRO) for many years because I could take my torch head anywhere and get a small cylinder of gas at the nearest hardware store. This was especially useful working in places I needed to take a plane to. The added advantage is that there was not a sizable tank of highly explosive acetylene gas in my shop. The best of the handheld MAPP gas torches I've found is a Sievert Powerjet from Sweden. http://www.sievert.se/products/powerjet/. It comes with interchangeable tips and has a pinpoint flame tip (#870201) that is pretty good. The standard tip gives a flame nearly identical to that of a Bernzomatic. They are not cheap, but you can occasionally find them on sale. I actually got mine from Farm and Fleet's website for a good price. I use it with a short hose to the cylinder so that I don't have to heft the whole thing. That came from participant comments at one of my workshops about the awkwardness of using the torch and cylinder together. I love the trigger start and basic simplicity of this type of torch.
My current torch is a Meco Midget oxygen/propane. I like it because it has a tighter and hotter flame than the MAPP torch, but not quite as hot as Oxygen/acetylene. It will let me braze steel in ways I could not do before, and the fuel is cheaper and more available than acetylene. I love the small size and great flexibility, but it was a real splurge to invest in it. http://www.tinmantech.com/products/w...dget-torch.php
The other torch type that has been the standard of mountmaking shops forever is a fuel/air jewelers torch such as a Gott or Prestolite. Usually these are fueled with acetylene, but I've wondered how they would do fueled with MAPP? Harris sells a turbo-tip version that is set up for MAPP and has a fairly small tip available. It seems like it should be the hottest small flame available from something other than acetylene. It would be interesting to hear if anyone has tried one out. http://www.harrisproductsgroup.com/e...fuel-kits.aspx
I know people sometimes use the small butane torches to do very small work, but I've tried them and not found them to be of much use. I'd love to hear of other people's experience using them.
The other thing you may want to look at is your choice of brazing alloy. The Harris Safety-Silv 45 has a liquidus temperature of 1370°F (743°C) whereas the Safety-Silv 56 has a liquidus temperature of 1205°F (652°C). I've found the 56 to be my favorite alloy formulation use it for everything. I also use tricks of building little corner ovens of firebrick to intensify the heat if needed.
Good luck finding the torch that suits you. It's a very personal choice. Please get in touch if there are other questions I can answer.
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