So what's the skinny on them? Seems to be an enormous difference in prices, I can tell part due to volts, part due to "pinned anvil" (don't have a clue as to what that means). Do they hold up? How long do charges last? How's the Craftsman one? Give me the good, bad, & ugly. I know DSR uses snap ons and they abuse the crap out of them but then again I don't forsee myself tearing down and rebuilding an engine twice a day every weekend day.