What's your favorite stove setup for brew-ups during a climb, that may turn into an overnighter? Pretend weight is a premium and cost is not. I'm looking for a combo of compact stove that works at high altitudes eg 5500-6000m (would bring a 200g canister), and a corresponding light Ti pot/lid. Probably need to make just a few (eg 4) liters at the most, as a stopgap.

I think for cold temperatures the MSR Windburner is going to be your best choice. I have not had an opportunity to use one, but it uses the same technology as the Reactor, which I have used, and it is pretty brilliant. The Windburner is about the same weight as a JetBoil PCS but the MSR system boasts better cold weather performance.