Looks like I am going after an old thread here so I probably won't get a response in time but here goes. I have been riding my 155 k2 astar for about 11 years now and needless to say am due for a new board. I live in the midwest but i make an annual pilgrimage to utah, colorado, or big sky once or twice a year. I am only buying ONE board.
I want a board that can ride extremely fast on groomers, will be able to float in powder when I am lucky enough to get a good powder trip, can maneuver tree runs and backcountry, and can hit the occasional table top and kicker. I never really hit rails or boxes so factor that in.
Right now I am leaning toward the 158 heritage based on these criteria but my big question I guess is how much control do i lose with the cobra compared to the heritage vs how much play do i lose with the heritage vs the cobra. If the heritage is completely worthless at doing 180s off natural features or tables then maybe the cobra is preferrable but if the cobra is going to get squirrley at high speeds than maybe the heritage. Which of the two boards is more versatile as far as accomplishing its weaknesses if that makes sense. I have a feeling i will be happy with either board since my current board is super old but I want to do as much research as possible before spending the dough.
I am 5'10", 190 lbs, size 9.5 boot.
Went from premier f1 to cobra last season. F1 was damp, carves well, and was rock solid at any speed. It was ssslllloowwww edge to edge. The cobra woke up tree and mogul riding for me, a lot. Also just more fun. Is it more squirrely at speed? Yes, but not until you break the 50 mph mark, and even then it's not like I'm afraid I'm going to get thrown off or anything, just not quite as point and forget as the f1 was.
Heritage I haven't ridden, but I'm betting it falls between the 2. I'm very happy with the cobra, and given the choice, would not a sacrifice any playfulness for added stability anywhere.
You could go with the 155, 158, or the 161. Since you're waffling cobra-heritage, I would think cobra 158 would give just that little extra stability that you seem to not want to lose.