^^^ The reason I run the 294 (with a WXC300 in the front), which are USUALLY overkill is that I figure this: If I am going to suffer the added drag of studs on dry pavement, then I might as well have a bit more drag and gain the ability to ride pretty much wide open in any conditions.
I had the side-studded tires for a while a few years ago, but having a bit less stud drag on the pavement didn't seem to be worth the sort-of-slip, sort-of-grip slower-speed-needed performance on glare ice.
I'll add the discalimer that about 1/3 of my winter route (has now been moved to) an very icy MUP, and the total route is only about 18km one way. If it was further I'd give up some grip for faster rolling and stick to cleared roads.