Originally Posted by Flintshooter

They are at their best heating two cups of water. That's perfect for most freeze-dried meals, and if you can work out some simmering method, they burn long enough on an ounce to do mac' n cheese and things like the various Knorr sides. Boil time for two cups on the ones I've used is usually under five minutes.
After a few decades using Svea and various MSR stoves, my initial impression of pop can stoves wasn't very high either. However, once you adjust to the limitations, they are hard to beat on a lot of levels. And, they are totally silent.
If you need to cook for a group or boil a quart or more of water at a time, you will need a gas or butane stove.