Go to for 3 seasons.
I've had my Cat's Meow for about 9 years now. It's been on countless trips in numerous time zones, spending weeks in its cramped little stuff sack, but when I take it out, each time it provides the necessary warmth and comfort that a solid sleeping bag should have. "A" for TNF on this one.
Complaint (one and only?): The velcro "pocket" by the chin, is really quite useless.
Just make sure to love your Cat's Meow (don't leave it in the stuff sack for months on end) and it'll love you right back for years to come.