I've done the look-thru-the-bore method when I could since I was old enough to know what I was doing which is the better part of 50yrs or so, just bought the laser bore sighter in the last year and I really like it!! If I hadn't got it on sale for $40, I probably would still be without it, but I'm glad I have it now. It's not anything like the old mechanical bore sighters if that's what anyone is comparing it to, not in the least.
Tim