I have a flip head, (it's what I prefer) and I have been using it for 18 years. There will always be good and bad reviews, but overall they are still good mixers. The Artisan will give you a slightly larger bowl than the Classic or Ultrapower, and more power to mix also, it should be a good choice.
Cuisinart is the other brand with a heavy duty mixer, many seem to like it, but it too has a few bad reviews.
One of the really great things about a Kitchenaid, is if you are handy, there are lots of videos on youtube on how to fix them if you ever need to, and parts are plentiful. There is one gear made of nylon that will fail to protect the motor if you are doing a bread dough or other thick dough for an extended period of time, this is cheap and easy to replace. I have never had to do a repair in 18 years, but I also know the limitations of my mixer. I make bread with no issues and lots of batters and buttercreams.
If you are going with a Kitchenaid flip head, go with an artisan model, it has the most power. The Classic is made for lighter use these days. With some shopping around, you should be able to find an Artisan for around $300 on sale.