The pancake does allow for more mounting options easier. Also mounted on a pack it makes it a bit more secure I think. But you can use a fold over and make it just as secure if you make it right and allow for all the same mounting options. I mold a band around the sheath to allow for extra mollie locks to make it more secure on the pack or to mount a teclok in the middle of the sheath instead of only on the side with the rivits.
Here is an example of what I mean for the fold over with the wrap
The option are endless with either syle limited only by creativity. Here is drop loop for it also