Are there any real advantages either way for actions that use cock-on-opening vs cock-on-closing? (other than what the user is used to?) Any safety considerations? How about cleaning/disassembling the bolt, I assume cock-on-closing COULD be made easier as the firing pin spring wouldn't be fully compressed as it would for a cock-on-opening action?

I've got one cock on closing gun, an 1891 Mauser. It may be that I'm not used to it, but I find it much easier to operate a cock on opening bolt. It sems easier to cock on the upstroke rather than the down stroke to me.

I collect and shoot alot of old military rifles, and have become a fan on the cock on closing. I like the fact that the ejection is much stronger, and I'm not so liable to short stroke the bolt on reloading.