Replying to Quiver question

I'm 5'8, 158lbs, and am a very aggressive skier. I live on the East Coast, and ski 60%park, 40% all mountain. Right now I'm riding 167 Chronics, which are my do everything ski. I love them in the park, and they kill it all mountain. I picked up some 174 Scratch Fs from SAC and still havn't mounted them. I dont want a floppy park specific ski.  so I'm going to keep my chronics. But my question is about the Scratchs. They have an 84mm waist, and would be my ski on a rare east coast pow day. I dont ski powder much at all, so I dont think i need a super fat ski, but I've only ridden pow before w/ my chronics. which are 78mm in the waist Will I notice a big difference between a shorter 78mm waist, and a longer 84mm waist?, or would it be to my benefit to trade them in toward a wider ski? Any input welcome, thanks.