You're poor antminer performance is likely either misinterpreted information or something incorrect with your rig set up. In spite of the recent system reporting problems the site is reporting accepted shares correctly presently for me. You should be able to cross check this value with your mining software for verification. With ants I recommend using bfgminer (latest build) as I have recently read the others may be experiencing issues with the units.
More likely the figures on Slush are wrong. I've got an ave of 1131992 Mhash/s on mine, but the 104275.221 speed has changed by less than 2% for those last ten...and CG miner has had a steady 145-154 range for the last month, I've been paying attention and it's only once been what Slush reported. That's quite a large difference, and if it's widespread ...massive.