A couple of thoughts. I think checking to confirm that a gun is loaded is a very good idea, on the range, when first holstering the gun, after reloads, etc. There are several acceptable ways to do it, many of which have been listed above. When press checking using the offhand under the forward portion of the slide, the serrations help most people most of the time. When doing it that way, your trigger finger can relatively easily feel in the chamber to confirm that a cartridge is there in low or no light. The overhand rear method is ok, but for some people it occasionally results in pulling the slide back too much, which ejects a round unintentionally, or, worse, causes a double feed or live round stovepipe. The use of the underhand forward press check seems to be a bit more controllable, as does the one finger under the muzzle method (which can't be done on some and is probably more dangerous, potentially). The comment that Ayoob doesn't allow press checking, which I cannot confirm, is to me explained and made irrelevant by the later comment that he runs a cold range (which I again can't confirm). As to press checking in general, my partners and I who operate a firearms school, have decided to not use it in the CCW permit classes, but do use it in more advance handgun classes. We found that really new students had difficulty in press checking safely, and in the limited amouht of time available in the CCW classes we felt we couldn't safely teach it. We do think it is extrememly important in general.