I feed mine in there cages. here's why:
1) after handling the snake to move him into a feeding tub he may be too busy checking out the tub to want to eat or just the fact that he was just handled may cause him to not eat.
2) it's not be a good idea to handle ANY snake that just ate. If hes still in feed mode he may go for you. Handling after feeding may also cause a regurg.
thats my 2 cents.