I have a kitchenaid toaster. it's brilliant. So I went and bought the blender, which is also brilliant but I never use it. I really want the mixer, because it is pretty, but I am trying to give up cake and it wouldn't help.
I have relatives that use US appliances over here, must admit they do use a bulky transformer but its not to bad. The transformer can be stored away in a drawer and brought out when using. If it saved that much I think I would do it. I got my mixer as a wedding pressie else would have seriously considered getting one abroad.
Classic is probably fine for your average baking needs. I've had my kitchenaid for 5 years (it's the old version of the artisan I think) and I love it. But I'm not sure you'd notice the difference between the two styles in terms of performance. I don't think I've ever used the highest speed setting. I believe the artisan has a bigger bowl, comes in more colours and has a faster motor (300 watts instead of 250). At least according to the US website. How much baking do you do?
I used to live with a pastry chef in the States (oh, the cakes) and she baked all the time with a classic. If it was good enough for her, probably good enough for us mere mortals. But I do like the pretty colours of the artisan....