dry cuts are best for people who's hair shrinks a lot when it dries. My hair doesn't shrink too much, but I do like to have it cut dry so that I'm sure it's even all the way around. If you have a lot of shrink, I would definitely ask for a dry cut, but if not than you could probably do either. (I'm not sure on this, so you may want another opinion)
As far as taking products w/ you, I'd say take them if you feel more comfortable that way, but be prepared for a possible fight if the stylist isn't on the CG bandwagon. When my friend went for a cut, the stylist lectured her for 30 minutes about not using a shampoo AFTER
complimenting her hair's condition and asking what she was doing to get it that way... :x
I go to a Devachan (sp?) trained stylist, but if I didn't I would just let the person use whatever, just to avoid this kind of confrontation.
And if your hair is already in pretty good condition, one shampoo or one time using a product w/ cones in it won't destroy your hair.
GL! Let us know how it turns out!