You are all correct, I own the Worldcup RC's in 175cm which I use pretty much strictly for racing. I also own a pair of Head Supershapes in 170cm (I actually have two, one is for sale) which I use on smaller slopes when I want to take it easier and in more varied conditions (I find them somewhat soft). I'm not into the one ski quiver, I also own a pair of 07 Head XRC 1200's in 177cm for use on larger slopes for more aggressive skiing on hard snow. Living in the midwest we don't get a lot of snow, man made hard pack and ice are the norm. The ski I'm looking to add would be used once a year out west, skiing lake effect snow in the northern portion of the state as well as spring slop and slush which starts here in February. I don't want a real wide ski, I wouldn't use it enough to justify it. I travel for business in the northern portion of the state and always pack the ski's, you just never know what conditions you will face and I travel light. I want one pair that will do it all as well as handle the once a year trip out west. When I go west I mainly ski the longer fast groomed runs but eventually on the trip it snows and there is always crud to deal with. I'm not really into soft snow and crud, I want a ski that will rip the groomed runs but get me through the crud with the least amount of effort!
You are talking to the right people!

Check my reviews under the Head & Volkl section at this forum. The AC4 and (I assume) the Monster 82 will be suitable. These wide skis are very agile under the feet of a good skier.
Cheers,
Michael