IMO, the technology is not yet there to replace
the firearm as a defensive tool for civilians. Although Taser's products are reliable -- they are well made, and they do what they are designed to do and perform to their design specs -- the limitations imposed by the present state of tech development are still significant.
The wires are a limitation, the probe spread question is a limitation, single-shot is a limitation (and drive stun does not help much in a civilian context), the prohibitive cost of practice is a limitation, and battery duration remains a limitation although great strides have been made there. Looking at the state of this technology now, it's already useful as an adjunct where firearms aren't available, and it's reasonable to expect continual improvement from this point.
The jolt of a Taser C2 (the "civilian" model) is painful, but it is not a pain compliance device. It achieves its results by "jamming the signal" from the brain down the nerves to the muscles, when the probes land on the subject and are the proper distance apart. And when the probes hit as they should, it really, really, really works. Unbelievably so.
Assuming your 'shooting' is accurate (get the laser aimed device, not the one without a laser!), the technical difficulty becomes a question of distance. As the dual probes leave the device, they begin to spread, reaching an approximate 2-foot maximum spread at the end of the wire (15 feet for the C2 model). Obviously, the further away you are when you activate the unit, the greater the spread, and the greater the possibility of one probe missing the subject entirely. The closer you are, the closer the spread, and the greater the possibility that the probes will land too close to each other to achieve full lockup on the subject.
If the probes land too close together on the subject, the Taser becomes a simple pain compliance tool, and no lockup is achieved because the signals aren't really jammed. If only one probe makes contact, no jolt happens at all although the current is running. In either of these two cases, you can tranfer to "drive stun," using the unit itself to complete a solid contact. The difficulty is that -- assuming you are able to get the unit solidly against the assailant's body in the first place, and aren't thrown clear and beaten to a pulp when you first try to make contact -- you are now stuck there, holding the unit against the assailant at close quarters. The very instant you let go, the assailant is fully capable of doing whatever he was doing when you started, only now he is very very enraged and you are still within arm's reach of him. If you choose not to let go, that battery is going to give out some
time. Now what are you going to do when it finally peters out? (The battery won't die after thirty seconds, but you will have to re-activate the unit to keep it going - better be quick! - and eventually the battery will wear down.)
The jolt from the C2 lasts thirty seconds compared to the LE model's five seconds. Thirty seconds is a long
time for the person riding the wire, but for the person running away, maybe notsomuch - esp since the assailant will be fully functional the moment the current shuts off, and since the retreating defender is now unarmed. Not to mention those wires, which can
be broken as the assailant falls, or if he is able to thrash around because full lockup wasn't achieved for whatever reason -- meaning thirty seconds is a maximum, not a minimum, and how far did you get before he was able to rise and continue his assault against you?
Used in law enforcement applications in typical LE encounters, they're a godsend. They can also be quite useful to a defense-minded ordinary citizen, even with the limitations mentioned above. But the technology still isn't there to completely replace the firearm as a defensive tool.
If it were? I'd agree that a moral person would not choose to use lethal force if a lesser level of force would accomplish the same goals. Once the technology finally arrives, a phaser set to "stun" is what the good people will use.