Yes the grinder is adjustable and when I need a new espresso grind, I will give it a try. I've never tried flavored coffee like what I saw in the store today and it's doubtful I will try it any time soon either. I do have carmel syrup and honey here at home and that's all I've used to flavor my latté's with. Maybe one of these days I'll get some vanilla syrup.
Although I'm not a big fan of flavored coffee for me, if I were to try a flavoring, a good vanilla flavoring would be the one I would try, too.