oh, well, no silver in them
seriously though, I would stay away from numismatic coins unless you're actually interested in collecting them. I have no idea how those coins will preform relative to gold, but realistically I would expect the % premium to decrease as prices increase (but what do I know). As such my advice from earlier still applies, krugs are cheaper.
I am kindof interested why the decision is between a krug and a double eagle, it seems like a rather odd comparison (also why I made a bad assumption).