There are many canister backpacking stoves on the market today.  All of them claim to be the best stove available today.  There are many factors that go into selecting the best stove for you. You have to consider the hiking temperature, wind speed, your hiking elevation, and whether the stove will be used just to boil water or to cook a full meal.  Most manufacturers are going to rate boil/cook times under ideal conditions.  All canister backpacking stoves are much heavier and require  a fuel canister .

The Gnat is one of the lightest stoves on the market.  But remember the lighter the stove, the more costly and less efficient it may be.  When evaluating gear I almost always use the metric system.  The metric system is based on the ten's scale, and you do not have to use mixed calibrations.  Measuring the weight in grams works best for me.  Most scales have both ounces and grams conversions.  I use a Weight Watchers' scale for lighter measurements and a postal scale for heavier gear.

 The Gnat has no wind screen or built-in igniter.  The Gnat by Monsanto is one of the lightest canister stoves I have found.  You simply unfold the arms and screw it onto a fuel canister.

The pocket rocket is a step up from the Gnat. It weighs slightly more than the Gnat, but it is more efficient and has a shorter boiling time.  It comes in a plastic container built for protection. It does have an ignitor for an easy start.

The Pocket Rocket comes with a canister stabilizer to keep it from tipping during use.

The Jet Boil Canister Stove comes with a pot and top combined with a baffled heat exchanger.   The pot sits on top of a burner connected to a gas canister.  It has an Pizeo ignitor to eliminate the need for matches.   An orange stabilizer makes the canister more stable on the ground.  A metal ring attachment allows you to use the stove with a frypan.  You can get a one liter or an .8 liter pot.  

Jet Boil with a one liter pot.  Canister stabilizer and cup also come with the stove.

At the top of the picture is an adaptor, which when placed on top of the burner will allow you use a fry pan or larger pot. 

Jet Boil burner with ignitor.

MSR makes a canister stove similar to the Jet Boil.  Boiling times are very similar.

The major difference is that the heat exchanger gets very hot and you can get burned if you are not careful.  The MSR also is very noisy and sould like a freight train.

The Jet Boil Titanium  was one of the lightest canister stoves manufactured, but it was taken off the market because of design flaws.  The titanium baffles used for the heat exchanger melted under extreme heat from the burner, creating uneven heating hot spots in the pot.  

Jet Boil makes a larger canister stove for used when cooking for larger groups.  The inverted canister improves the stove's efficiency.

The fuel is also preheated for better efficiency.

A larger pot, carrying curtain and top with flip lid come with the larger stove.

 The liquid fuel stove is an alternative to the Jet Boil for use in extreme cold weather conditions.  It is much heavier, but it functions well in freezing temperatures.  Canister stoves have a tendency to freeze up and be less efficient.