I, too, thought that it would slow down the draw considerably, but I have been collecting data as I have been practicing and while I can draw and fire one shot in, on average, 1.64 seconds with my shirt untucked, it only takes me 1.69 seconds with it fully tucked. The times are slightly more variable with the shirt tucked, but I think that as I practice more, the added concealment will come at almost no cost. If I wear it under a t-shirt, the steel is a little cold for a moment or two
but from a comfort perspective, I think that they are great! I am looking into adding a velcro strip to my belt so that I can make and use some velcro clips and that will take the stealth factor up 2 or 3 notches, as the rear clip is the only "tell" that this system currently has.