Okay Mh/s is for scrypt minig (litecoin/dogecoin)
G/hs or T/hs is a miner for Sha-256 (Bitcoin/peercoin)
Greed seed are scrypt miners, not a bad option if you want to mine lite and dogecoin(I'm actually debating buying one of the 350kh/s units just for fun to mine me some doge).
It's very important you choose the right miner for what you want to mine, a scrypt miner can't mine Bitcoin and a SHA miner can not min scrypt.
$28 a day sounds about right, with 720 G/h I'm earning pretty much what coinwarz says, give and take depending on luck.
ok thanks for the explanation. 1th/s sha-256 can be compared with how many mh/s scrypt value (being also in same price range)?