Had an Alpine160 (I know the 6 is even longer and slacker), now got a Rocket.
Loved the Alpine – so easy to ride on steep, rough stuff. Pedalled OK with a decent shock setup.
Love the Rocket just as much – not as easy to go fast on, but a much more involving (IMO) bike to ride. It actually needs riding, rather than just sitting on (which is what the Alpine felt like at times), and for me that gives it the edge. Looks better too (although I did grow to like the Alpine’s industrial chic).
I don’t think you can go wrong with either bike, but if you want something a tiny bit more ‘all-round’ then I think the Rocket is the one. If you’re more gravity-oriented then it’s the Orange.
EDIT. 5’6″ on a small (16″).