IMO, the taser fills a 'hole' on the FC outside of LE - espeically for those who do not carry firearms.
There are a number of states that have made the devices illegal for non-government possession.
I am also a certified Taser instructor - I want to address some of the information posted in this thread.
The X series Tasers are smaller than a lot of commonly-carried handguns. That said, I really don't have room on my body to conceal more than one handgun-sized object. I wouldn't leave the firearm at home in exchange for the taser. Your situation may be different.
ALL Taser cartridges have the 'confetti'. These are called AFIDs, for 'Anti Felon identification'. When you make the purchase, the ID number from each cartridge is recorded.
The Tasers are expensive, yes. However, if you lose your Taser in a self defensive application (and you should if it is deployed as directed), Taser (the company) will replace it when you submit a copy of the police report. In that light...
The 'citizen' taser has a 10 second cycle time and it can be increased to as much as 30 seconds with a couple additional presses of the trigger after deployment. The taser is then placed on the ground while you make your escape. (I am not going to argue the merits of this tactic - certainly it can be what-if'ed to death)
The taser is a short range device. The cartridges available to non-governmental personnel only contain 15 feet of wire. (LE can get 21 and 25 feet) Of course, for a justified claim of self defense, the distances are going to be short anyway.
The arc can go through 2 inches of clothing. Heavy winter coats do represent a potential problem.
There is no evidence whatsoever of a Taser discharge ever causing heart damage. If you look at the Taser's current curve, it is well under the limits established to cause fibrillation.
Tasers are available in black and 'safety' yellow.
Here are some pictures:
XP and 'standard' probes.
M26 model with arc - no cartridge installed.
Here are the different cartridges.
Randy