I have a SIRT and love it. Even though I own more M&Ps than GLOCKS, I went with the GLOCK version because as someone pointed out "a striker fire trigger press is a striker fired trigger press"
I've got to say, i think that having: (bolder are the things I think are REALY important)
-feedback of how good my trigger control is
-something that I don't have to worry about being loadedy
-something I don't have to clear and reload
-something I can leave laying out on my desk
-something I can just pick up and get as many or as few trigger presses in durring a session as I want, regardless of time of day, and without my room mates hearing the distinctive pistol slide racking
-something that lets me practice my reset without racking the slide,
-something that lets me practice reloads without unloading my carry magazine
-did I mention that I don't need to worry about where I'm pointing it? So I can do things like use the squirrels outside as targets?
Is all a good thing. I think dry fire and practicing the drawa with the actual carry gun are important, but I think that the SIRT was worth every penny I paid for it... Not a lot of things I own that I can say that about.
Another benefit of the SIRT is that's it's fun! Not just for me, although it's a major bonus, but over Christmas, even my sister (not a hard anti, but she continually turns down any offers to go to the range) wanted to try it!