Thanks for the advice, folks. I appreciate all the advice I can get.
Billiam -- I've skied the Head you mentioned, as well as the Head Big Easy, and haven't liked any of them. That could be because I skied too short of a ski -- I skied the 178s -- but neither ski was pleasant for me. I'm going to ski the Super Hot tomorrow, as well as the Fischer Big Stix 7.6. If I can, I'll try to ski a Salomon of exactly the same dimensions as the Fischer, so I can get a good comparison.
You're right about the crud-busting abilities of the Explosiv. One disadvantage of being an inexperienced skier is that I struggle when conditions change -- when I go from groomed cruiser to off piste moguls, for instance, or from steep powder to sticky mush -- and the Explosiv smooths out the transition very nicely. It's nice and smooth on any kind of snow. I'm still skidding my turns way too much, so I'm not really bothered by it's disadvantage on the groomers. This ski opened up a lot of the hill that I really struggled to ski on a narrower ski.
AT -- You're advice is good, but I'm way too much of an equipment junky to wait another year to buy a new ski. Besides, the ski I own doesn't work for me nearly as well as some I've rented. As I find that a lot more of the mountain is accesible on different skis, I'm pretty sure that I need one.
I've tried two or three different mid-fat skis, with mixed results. I'm going to ski on a few more this weekend, so I should know what I want by the time people start selling this year's equipment.