RedDragon and I use a combination. For example, our BCIs are just too aggressive after feeding, so they get fed in-cage. NEVER been bitten by either. Then again, we've had the female for all of 3 days now, and only 1 feeding, but I digress.
The female is on newspaper, so no fear of substrate ingestion. The male is on bark, which is big enough not to worry too much about, and we feed dry prey so nothing sticks.
The VBBs also get fed in their enclosure, because they get scared when we dangle prey in their faces. I put the mouse on a feeding dish inside their hide box, and check on them an hour later.
The adult corns get fed on the floor. They have smallish enclosures, and NEVER bite after feeding, so we put them on the herp room floor and transfer them back to their enclosures when they are done. Never had a regurge or a bite.
For the neonates, we do use a feeding box, as they have ingested aspen before. Besides, it's a great way to get them to take the prey if its just them and a mouse in a small tupperware container.
Same with the Kenyans - good ol' feed bucket in a dark closet t eliminate risk of substrate ingestion.
So there ya have it. We feed in-cage when we can, out of cage when it's more practical to do it that way.