When we hunt the family farms, we gut when we get the deer back to the barn. That means from 20mins to about an hour, depending on which farm. We do not field gut, but keep the meat clean of any ground clutter or foreign matter. Why drag an open wound through the woods? I've never seen any issue with the taste of the meat due to the slight delay. We gut in the barn, and drop it all into a wheelbarrow, and deliver it to the gut pile. It serves double duty, if we set leg hold traps around it.
We've done no gut version, but in general, we prefer to gut it, wash it and hang it a couple days if the temps allow. The only time I ever use a processor, is if I do not have time to do it myself, such as a Sunday evening hunt.
