I am a 17 year old backpacker trying to go lite for this season. I am on a very limited budget and want to make the most of my purchases. I missed the recent REI sale but i found an new REI sub kilo 20 for $150 on eBay and am wondering if i should purchase it. It would be by far my most expensive piece of gear but i hear it is a good bag. I hear the temperature rating is more like 30 but i don't plan on hiking below freezing very often.What do you all think? This is a very large purchase for me? Any advice would be helpful! Thanks.