I have never fed in a seperate container, and unless i need to i never will. When it comes time for feeding day, i get the little rodents out, make sure they are good and dead, then go in and take all the cage furniture out of the enclosure. Hides, waterbowl, branches, and fake vines all get washed at this time. I just drop the little dead rodent in, and wait until after they finish eating to replace all the stuff. I havent had a problem yet with any of my bp's associating my in their cage with feeding.

What are you using for a substrate? You said you were worried about impaction. That would be one argument for feeding outside of their enclosure. I use newspaper or paper towels so i dont have to worry about that. Remember, its all up to you. Each keeper and snake is different.