I like the white lightning over the Allan or even the screwdriver slot, and only then cause it blends in with the barrel.
I don’t worry about pulling one back out cause I can’t think of a reason one would pull it.
However you could pull it if needed with a slot or Allan where as I would ruin a white lightning getting it out.
My thoughts on that are this:
If the liner NEVER needed to be removed (or replaced) then there would have been no reason to do anything but drill a hole in the first place.
However - it is a fact that under heavy or long term use - that drilled hole will enlarge and eventually be a problem.
Those who claim they have not changed or removed a liner in XX number of years - likely don't put a large number of rounds through the gun.
I do not remove a liner every time I clean up after a trip, but I have burned out a liner on my favorite gun and had to replace that liner.
Had it just been a drilled hole, it would have then been drilled and threaded for a liner, but since that was done at the factory - replacement was a fast and easy 5 minute job.
And there was one situation where I helped a friend who did not understand a patent breech very well and "cleaned" his gun and left a solid plug of junk in the channel, that one had to be picked out from both angles to get it clear, good thing that one had a liner too!
So I see both points of view, and in todays world 99% of all flintlocks have liners installed, on one type or the other. I like having the options of removing the liner especially since almost all of my guns have a patent, semi-patent or some variation of that undersized channel that makes it a nice feature to have.