I'm at nearly 6BTC mined over the last several months at middlecoin.
Just FYI: my average over the last 14 days at MC (actual paid to my wallet, not unexchanged/immature): 0.016295714 BTC/MH
For comparison:
14 Day Wafflepool average: 0.01116903 BTC/MH
Can't find long-term stats on any other pools to compare to, but I expect the law of averages still favors MC.
That's my experience, too. I've been earning a little less than that pointed at the EU server mostly; is your average for the vanilla middlecoin server?