I've been using one for just over two months now. For me, the Kramer Confidant works just GREAT.
I've been carrying a SIG P239 in .40 in mine. This may be getting toward the upper-limit of realistic carry for this shirt, but I think I've read of folks carrying up to Commander-size 1911s in them. More commonly found would probably be smaller autos and snubby revolvers, I'd suspect.
I normally wear a size XXL shirt. I ordered my Confidant in size L for a good, snug fit. I wear it over a good-quality heavyweight cotton tshirt, then put on one of my normal button-down shirts. The rig works with anything from short-sleeve casual shirts to long-sleeve business oxfords. You could certainly even cover it with golf or polo style shirts, but that would tend to further slow down an already pretty "slow" rig. The Confidant is obviously not built for speed but it is exceptionally versatile.
This is actually my favorite setup for church carry and for anywhere I want to go where I want to wear a shirt tucked-in and not have to deal with a covering garment...I actually really like photo-style vests and such but I sometimes need a break from them!
You can pick from a full-length shirt that is able to be tucked-in (that's what I opted for) or a 3/4-length shirt that would catch you across the middle of your stomach. The neckline of the shirt is cut low so that it won't show at the neckline of your regular shirt...only your undershirt will be visible, just like normal.
On me, the SIG seems to disappear when I'm wearing the Confidant. Yes, if I bent way over and to one side "just so" and someone who was really dialed-in knew where to look...they'd see me print. But I've had a few of my gun pals do double-takes when I tell them I'm packing a .40 SIG and they see me standing there in shorts and a tucked-in shirt, with no fanny pack or photo vest present!
For me the Confidant has been very comfortable and easy to wear. I've gone for up to sixteen hour stretches in this thing with no problems at all. After an initial four-hour breaking-in period (the grip of that SIG being so high under my arm took some getting used to!) the ease of wearing this thing has just been incredible. I honestly rank this as one of the best gun-related purchases I've ever made.
A couple of points...First, if you live in a humid climate, you will perspire all over your weapon when you carry it in the Confidant, so a corrosion-resistant finish is preferable...Second, give some thought to spare ammo. If you're going to carry reloads at all, you might be able to pack them in the offside holster pocket (this assumes you're only going to carry ONE gun in your Confidant...you could certainly carry two...the thought of two sweet little .357 snubbies in one of these shirts is a happy thought
)...but, for ammo, you might have to get a little creative with a needle and thread on that other holster pocket to make it work. I think I've read some earlier threads on this where folks have managed to attached single and even double mag pouches to the shirt itself. For some reason I could not get this to work and still be discreet for me.
While my SIG has a great blackened stainless slide and an alloy frame, my factory mags for it are all blue steel. I tried carrying a spare mag in the offside pouch but it kept getting surface rust on it from sweat. So, I opted instead for a cheap little Uncle Mike's black nylon single magazine / knife pouch, and I carry one spare mag in this in a trouser or shorts pocket.
Well, sorry for my lengthy dissertation here! I should get some sort of commission for this endorsement, shouldn't I?
I do hope you get to try one out. Oh, and do a search on this rig...I recall from some earlier threads that another holster maker is marketing a similar product to this and it looked like a pretty good setup, too.