I just picked 20m radius and 25m out of the air because the numbers printed on the ski don't mean much, actually skiing the ski means a lot more.Not much difference between 23 and 25. Big difference between 25 and 45 or 50 or 70.
Grouping skis in a category based on width under foot is kinda inadequate because it ignores tip and tail width, tip shape and rocker.
Sizing ski length by skier height is kinda lame as well because skill level and skier's weight are more important.