I plan on Trading in my Pardner which will fetch $100 towards buying a used pump action. Question is the place i'm trading it in at has a Mossberg 835 with the 3 1/2 inch barrel thats in fairly good condition and a Mossberg 500 with just the 3 inch barrel thats in a little better condiiton and he 500 is around $150 and the 835 is about $165, which one should i buy?

Please don't tell me to buy new because i don't have the money, i just wondered if that extra 1/2 inch matters that much for duck and goose hunting or if the 3 inch barrel would suffice.