Is My Snowboard Too Big?

So I just bought a new Burton 165 Wide snowboard, but I am not sure if it too big or not. I am 6'3" 200 pounds with size 13 feet, so I'm a pretty big guy. The board is about an inch below my chin and is pretty flexible with Burton giving it a 4 out of 10 on their flex scale (1 being the most flexible and 10 being the least). Basically I would be mostly free-riding on the mountain, and maybe hitting some jumps here and there but no serious park riding. I'm just not sure if I will be able to handle this thing or not. Will I be able to carve, turn, stop, etc? I'm just afraid I'll be shooting down the mountain (as I know longer boards are faster) without the ability to really carve it up. What do you experienced riders/instructors/ski shop workers think?