I have two ATR's and like them both very much. I've looked at and considered purchasing a 4X4 based on my experiences with the ATR. I consider the 4X4 a fancied-up ATR with a longer barrel. I don't like it enough to pay the additional cost for a caliber that is also offered in the ATR. I would give the 4X4 much more consideration if I decided I needed a magnum caliber.
The choice is a personal one. If you are considering a 4X4 and like the rifle, that would be a good enough reason the buy it.