User Review: Primus EtaPower EF
Price Paid: $54
This stove burns so hot and boils incredibly fast. The heat exchanger design on this baby is second to none. It is not small, however, and its designation as a stove for 1-2 only applies if you have the appetite of an offensive lineman in the NFL.
But if you are camping with anyone else, tell them to leave their solo setup at home and your ETA will take care of the rest. I've only tried this stove in sub-freezing temps, at 8k plus, and was surprised at its efficiency. I boiled snow in minutes (so fast, even at elevation) and was amazed at how low I could adjust the flame to keep a pasta sauce simmering low. The included case kept the cooked pasta plenty warm until the sauce was done.
As the temperature dropped to about 20 degrees at said elevation, the efficiency waned a little. I've since developed a neoprene sleeve for the fuel cannister and I have a thermal wrap for the hose. I'll be interested to see if that keeps the fuel temp up and maintains efficiency.
Despite its size, I was able to store a 250g isobutane can inside, along with some packets of instant oatmeal and all of the parts (including handle clamp). The included cloth designed to protect the pans from one another also doubles duty as a hot pad. I cooked two large meals for 4 (including coffee, tea, and hot-cocoa) and used very little fuel overall.
I could not be more pleased with the whole setup and I'm planning now to buy the ETA express (true solo unit with all of the excellent design features of the ETA Power). If you can afford it, buy the new Multi-fuel version of this stove. It's supposedly even more efficient and can handle even colder temperatures with its fuel flexibility.
Update: March 23, 2010
As a follow up, my last review commented on the efficiency waning a bit below 20 degrees. It may have a little, but the pasta that I thought should only take a 6-7 minutes to cook (Barrilla protein pasta-bow tie) takes 15 minutes plus to soften to ideal texture...so it was not the cooking system after further investigation (buying the pasta for a home-cooked meal).
Neoprene sleeves for the canister and fuel line neutralize the effects of freezing weather on efficiency, even down to single digits.