I carry the G30 SF in the Comp-Tac listed above. They do offer metal clips, but with the plastic clips and a decent belt I have had 0 issues. you can adjust the ride height and angle it rides inside the waist. The G30 is a bit larger than the G27 and I have had 0 issues with concealment or anyong noticing it. Draws easy, even worn at the 4-5 oclock range. I set it fairly low and even if my shirt rides up there is not much to be seen. The belt pinches on the Kydex and keeps my jeans/belt from interfering with the draw, everything sits very snug. I wear it all day around the house, in the car, shopping, etc. I forget it is even there. Not very easy to re holster it, but I don't plan on needing to ever do that quickly.
My brother has a G27 and the Comp-Tac holster and is totally happy. I believe he has one for his 3" 1911 as well. As mentioned, it is nice that you can order differnt kydex sheeths to change your holster for different guns. The adjustablity of tension also works nicely, and the sheeth covers the entire trigger and gaurd so you won't get an accidental trigger pull. Other holsters have similar layouts, but the more I wear mine the better it gets.
That being said, I stick with what works for you. If the super tuck has been that good, get another one. I have read many good reviews. The G27 is a great carry piece and the .40 S&W is a fantastic round. Can't go wrong with Glock. I have put thousands of rounds through my G30 of all sorts and never had an issue. Solid choice all around.