I've owned way fewer semis than revolvers over the years . . but a few of the semis I've owned have had loaded chamber indicators. To be perfectly honest . . . I've never paid any attention to them one way or another. Not being "flip" about it . . . I just always treat the handgun as though there IS on in the tube unless I've locked the slide back, dropped the mag and cleared the piece. But then I'm a little weird about "counting shots" as well. I was trained many, many years ago on revolvers to count the rounds going in to the cylinder and to count the as fired. I do the same when loading mags and shooting semis. I'm amazed sometimes at the range when I see folks that don't follow that practice whether it be a wheelmen or a semi. Whenever I work with a "new shooter" - that's one of the first thing I hammer in to their head - count your rounds in and out - then treat the handgun as if it is always loaded unless you've cleared it.