The "its costs more to make the actual value" argument is interesting but doesn't really mean anything. All currency gets used in many transactions, so whatever it costs to make is irrelevant compared to potentially infinite transactions it will facilitate the help fuel the economy.
The clincher for me is the the penny and other small denominations of money are grossly inefficient at their one purpose: to facilitate transactions of stuff. Physical money is divisible into smaller denominations so we can fine tune the exchange price, but it isn't divisible infinitely. At some point the denominations become too small to matter to the exchange of stuff.
The US has already encountered this issue with the half-cent ($0.005) which they discontinued in 1857. +/-$0.005 didn't change the effective value of any good or service, so it was done away with.
These videos are very interesting and informative...