Yet for all its practicality you just don't see enough alpinists using heat exchangers. So as a public service, as the poet-philosopher Eminem likes to say, let's do the math. The XPD heat exchanger will increase efficiency "up to 25%." Let's say it's only 10%: a quick two-week jaunt up Denali works out to at least 6oz of fuel per person per day or 6*14 days = 76oz per person. At .75 dry ounces per wet ounce that's .75*76 = 57oz of weight.
10% of that is almost 6oz per person, coincidentally what the XPD weighs. For a larger party and more time you just save more weight, especially if its the difference between carrying another fuel bottle or not. Plus cooking is more efficient, saving precious time and allowing you to collapse into your fart sack faster. The XPD fits even a 2L pot and collapses to fit inside. What's not to like?