So, that's the big hurdle covered. As to your other questionwhether the cheaper fuel will work wellthe answer is: Sure, it'll work fine. The Glowmaster cartridge uses butane, isobutane, and propane, a common blend that extends the optimal burning temperature and helps ensure good performance up until the canister is almost empty. Obviously, this beats having the thing do a slow fizzle once it hits the one-third mark, which was the norm 20 years ago. The exact gas ratio is a closely held Glowmaster secret, but almost certainly something in the order of 50 percent butane, 30 percent isobutene, and 20 percent propane. In other words, it's very similar, if not identical, to the MSR fuel. Fuel weight in the canister is the sameeight ouncesso burn time should be the same.
Based on the above, my advice is to go ahead and buy yourself one Glowmaster cartridge, try it, and, if you like it, buy some more.