I've been using the Weller Pyropens for many years and if expense is no concern then these are still my first choice for field work. I have found them extremely effective in tinning larger gauge wires and where larger solder pads or connectors require additional heat, they are also brilliant for working with heatshrink.
They are however prone to a few inherent problems such as ignition failure and if left unused for long periods they can gum up which blocks the butane flow altogether, both of these issues can be easily addressed in the field with a gas lighter in no time and little risk. The diameter at the base of these pens also fits nicely in a spool of solder which can act as a stand.