Snowboard Size ? ... Bataleon Goliath 157w or 161w?

I plan on purchasing a Bataleon Goliath, but not sure if I should get the 157 Wide or 161 Wide. I'm 6'3 and 190lbs. I want to be able to have a board I can carve down mountains and hit some rails,and I know the shorter the board the better for Park. But not sure if 157 is to small for me. Thanks