Hard-sided coolers: These range from the old green Coleman coolers—once a staple of every camping trip—to Yetis, which cost as much as cars did when Coleman started making coolers. Rotomolded coolers offer seamless, uniform density in their walls and lids, which drastically improves a cooler's performance. Soft-sided coolers: Soft-sided coolers include everything from well-padded, impressively insulated sling bags to roll-down, dry-bag-style coolers perfect for those mild beach days.