I think they're fine-- for anything but carrying. Not that big a deal, if a guy wants to carry one he should, but I never cared for one myself just on account of the noise increase / blast hazard being too high a price to pay for a slight increase (slight because it is, after all, by definition a smallish comp) in shooting speed.
Comparing Second Chance times, between Pin Gun and Stock Gun categories, and remember many of these comp guns are big honkers, heavyish guns with big comps with big ports, you will find that broadly speaking, Pin Gun times run well less than 1/2 second faster than Stock Gun times, and that's for five pins. I'd have to look again when I get a chance but it is well under 1/2 second (I'm thinking more like an average of .2 actually). Of course this varies widely due to many factors, but I know my own times were generally .1 to .2 different.
As long as you're shooting with arms extended you're OK, but if you fire from retention or with the thing right under your chin like in a struggle for the gun, you're both gettin' a contact wound....