Down vs synthetic sleeping bags

Synthetic:
Cons- heavy, large volumn when packed
Pro- cheaper, possibly more durable short term, possibly warmer when wet

Down:
Con- expensive, possibly more easily damaged, won't keep you warm if soaked
Pro- lighter, packs smaller, lasts longer if well treated

Personally, I would recommend that a college student look at a Campmor 20 degree down bag, an REI sub-kilo on sale, or order a Ray Jardine quilt kit (synthetic) assuming that you will be camping out down to around freezing. If it never gets that cold you have a lot more inexpensive options.
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If I wouldn't eat it at home, why would I want to eat it on the trail?