I switched to mapp gas several years ago when I was running a lot of copper, repipes, and remodeling work in our last house in socal.
I keep an old propane outfit around for backup and odd jobs like brush burning that doesn't require premium gas.
mapp as everyone knows is hotter burning. most noticeable advantage it heats your work up faster and subsequently more localized, reducing heat migration to nearby joints, fixtures, valves, clamps, etc.
slower propane heat takes longer to heat to working temp and susequently spreads further from your work.
higher heat is also handy for heavier material, low temp work, and of course faster if working a lot of joints on bigger jobs.
the mapp is gas is slightly more expensive than propane but the gains in the amount of work you get I think puts you ahead.
I've had that TS4000 igniter for years and it works great. it's fixed flame output for copper work which is all I really do with it. I use oxy-acetylene for steel work.
you might find the variable flame TS8000 more versatile if you have other uses for it requiring the highest heat output.
either way, the push button igniters are handy! especially contorted upside down under a sink juggling tube fittings, paste, tin, etc. without setting your house or your britches on fire.
good luck!
