I wanna get one soon. I'm not interested in anything other than Casascius. That's the
gold standard and that's the face of bitcoin to the rest of the world in a way so they'll be the ones worth my money.
that would be the "bitcoin standard" 
Some of the others are kinda cool but they're nothing but curios in comparison. No one's gonna care about them or know what they are in 5-10 years. They'll be lumps of metal with a bitcoin stuck to them.
Maybe, maybe not....Any coin is just a lump of metal and this is just another side of coin collecting that happens to have an added bonus feature.... 
I don't see how some of the premiums can hold if the price rises but I don't really care. I want one as a long term investment.
Even if bitcoin itself dies they'll have historical value.
Might I interest you in some nice Zimbabwe dollars 
I bought one of those years ago to have Ron Paul sign. After just looking what those are selling for now I it seems I should have bought the stacks that were available at the time.
As far as physical coins what I like best is the opportunity they present to talk with others about bitcoin who otherwise would blow the idea off.
