Does the % of Isobutane and Propane make that much difference, in any, to stove performance? Is there a blend that would work better at lower temperatures, or at higher temperatures? Would one be better than the other at sea level or higher elevations? Does the difference in BTU's of butane (102,032/gallon) and propane (91,600/gallon) have any impact on stove perforrmance? Anybody have a manufacturer preference or one to be avioded?

MSR - 80% Isobutane, 20% Propane
Optimus, Brunton - 70% Isobutane, 30% Propane

Thanks, Rick