Fallout: New Vegas Gun Guide - Incinerators
EDIT: On PC the Heavy Incinerator can fire 3 shots in VATS, although this is a bug yet to be fixed.
Doing a double feature since the difference between these two heavy weapons is much smaller than you think. Both of these weapons are something that in my first few playthroughs I ignored but as I play now I realize its a great weapon for a budget Courier and with the Heavyweight and Pyromaniac perk these weapons can be a cure-all for all problems, especially with the Underworld section of the A World of Pain mod giving access to a deadly Heavy Incinerator Mk. III which is the perfect weapon for the arsonists.