Confession: I was nervous diving into the 20-degree Klickitat when the forecast called for below-freezing temps. Its uninspiring loft just doesn't say "sweet dreams." But I stayed plenty warm, making this inexpensive sack one of the year's best deals. The trick? A new synthetic insulation, called Climashield XP, that has surprising warmth-to-loft. Plus, it has a fat, heat-trapping draft collar. 20°F, 2.7 lbs; coleman.comBonus: The bag's liner is treated with an antimicrobial agent.Bummer: The draft tube could use a touch more fill.