ORIGINAL: stickin8s
If your shots are going to be under 30 yards a moss. 500 will work, but if you want to have a fighting chance, then I would use the rem. 870.
I've got both a Mossberg 500 and a Remington 870. The Remington 870 has never killed a turkey. My son used it once, and missed. On the other hand, the Mossberg has a long history of dead turkeys -- over 30 yds. I have a choice which one to use every time I go. I always pick up the Mossberg.
Hal