I'm not terribly familiar with the VMII holster, but what kind of clips do you have on it to make it tuckable?
I have a Dakota Defender from K&D which came with standard clips, akin to those pictured
here. While they worked, they stuck out like a sore thumb, atleast in my mind. I ordered a set of
C-Clips from Comptact to replace them, and am very happy. The new C-clips are almost completely invisible on my belt line at anything but a scrutinizing examination. I'm not sure how the kydex clips attach to your VMII, so I don't know if these can be put on that particular holster or not.
In terms of actually wearing the gun, it is a bit different than a standard IWB, IMO. I tend to wear the gun a bit deeper in the pants, minimizing the grip extending up over the belt-line, but still leaving plenty for a good grab in a draw-situation. A bit of experimenting with the mounting positions was all that was needed for getting a comfortable carry position. The lower carry position will minimize the likelihood of the grip being readily identifiable on your side through the shirt.
On of the biggest problems I have found in wearing a tucked-holster is that I find the shirt can bunch up more in the holster and clips than on the other side. It requires a few extra seconds when getting dressed to make sure that my shirt is on straight and not clustered around my gun. A minor inconvenience, but one to note, especially when wearing shirts with long tails; the more fabric to jam between the holster and clips, the more of a pain it can be.
Also, while carrying tucked, be aware of your body movements. Bending can make the gun print more, since the bottom of the shirt isn't able to swing out to accomodate the movement, instead being pulled taunt over the gun and printing. Allowing enough excess material bloused out of the belt will keep this from happening, but you don't want to leave so much out that you just end up looking slobbish.
One last point is about the shirt itself. As with any carry, patterened shirts will minimize printing more. I tend to only carry Tucked these days when wearing dress shirts, which are always solid colors for me, so depending on your dress this may or may nor be an issue. You may want to look into striped shirts instead of solid colors, but I just don't like 'em.