I have never had a twist switch fail, cannot say the same about click switches. I prefer things to be KISS simple when something that my life may rely upon is concerned. And in my personal experience, they are more reliable, your mileage may vary.
Even the click switch on my L1T is working incorrectly and it is about a month old. Yes, I am sure when he gets back with me 4Sevens will make it right, but that does not change the fact that it is another click switch that has failed.
Now I have the L1T turned on with the clickie, and then the tailcap loosened so I use it as a twistie, more reliable that way...