I have been riding a 152 subzero for about a whole season now, and I love it. Its super soft, and very easy to butter with. If you don't detune the edges a lot this thing can def handle the whole mtn. Maybe not as well as a super stiff dirrectional board, but it can hold it's own; in the end it is the rider that counts =). It can handle larger jumps as well, but it's just better if you land bolts. It is awesome in the pow and i really have not had any problems with it at high speed. If you don't detune your edges at all, this thing can def lay down some trenches.
I have not ridden an artifact rocker, but i hear they are not that soft.
After a whole season of park riding my board has held up really well. The top sheet seems to be tougher than other brands i have had (rome, capita, omatic). If you are looking for a softer park board, i definately recomend it.
im 6'0 140 lbs and 10.5 DC boot (size 10 in every other brand though) used with L/XL union contact SLs.
152 would fit you well.
you prob can't go wrong with either board though.