Krugers are vastly better known, thus easier to sell and buy. Everyone knows a Krugerrand, I don't know a buffalo from a bison. Except you can't wash in a buffalo.
I love the look of the Buffalos. I bought as many of the '08s as I could when they started going dark in late Dec. of '08. Sold 'em all when gold was $1,800 an ounce.
If you are looking to convert dollar bills into gold, Krugerrands are the best bet. Hands down. Same amount of gold As a buffalo, 1 oz, but a much lower premium. Will you recoup the Buffalo premium when you sell? Maybe. Maybe not.
I thought the buffalo was created as a more "Pure Gold Coin" over the Kruger 1 OZ of gold in each but the quality is better?
I'm biased. Krugerrands are my fav Coins. Both contain 1 oz of gold. Buffalos are .999. Krugerrands contain a small amount of copper, giving them their awesome color.
If you're in the U.S. go with Buffalo's. Buffalo's will maintain the small premium they have when buying and selling whilst the Krugs will not maintain any premium at all and get treated as generic bullion.
I would never buy a Krougaran, suspecting them of being fake. But I do own some Krugerrands. They sell for less than other one ounce bullion coins, but they also cost less. Only the percentage counts.
How about diversifying and buying one of each? If you watch the ebay daily deals page*, you can get some nice deals and pay using a credit card (so another 1%-2% off via rewards points). I have seen Krugerrands for as low as $20 over spot per oz (not BU though) and Buffalos in the $30-$45 over spot range. Gold Eagles are another good option. If you are selling in the USA, Gold Eagles and Buffalos will do better. Worldwide, Krugerrands could be better. *For example, this gold buffalo is $33 over now: http://www.ebay.com/itm/SPECIAL-PRI...KU-118011-/142256622584?rpp_cat_id=5000006556