A drill bit is of course beveled over it's entire tip, and will remove a good bit of the back layer. Not an insurmountable obstacle, but not necessary.
The hole saw cutter, as mentioned, have to be quality items. They have to be used at slow drill RPMs and gentle force, leave a circle of the upper layer that must be ground off, and frequently drill a smaller hole virtually all the way thru. I don't see the point in them.
The cutter that looks like a drill bit with an almost entirely flat end still has to be operated at low drill RPM and gentle force to last, drill a smaller diameter divot in the back layer, but if used right otherwise leave the back layer alone. I have had awesome success with these.
I like the cutters that look like a flat ended drill bit, with a variable speed drill, patience, and lots of time to do the job.