Murphy

I got a box of 2005-P Buffalo nickels and thought I'd try to find a Speared Buffalo. I looked through 10 rolls and didn't find any of those, but I did find two varieties. One has a die break running from the lip to the bottom edge of the coin. I guess you could describe it as a spiked chin. The other variety has a cud in the top if the "N" in the motto. I have found over a dozen each of these identical coins. My questions: are they actual varieties and are they worth keeping? What kinda things do you look for in varieties, besides Doubled Dies & Repunched Mint Marks? Thank you. (I don't visit here enough, but this is such a cool forum!)