I was working in this megatypers captcha entries and it frequently says that you are kicked off (eventhough it says image will load in 5 seconds to enter) and wait for some time. After two warnings, my account got banned permanently. I had 95.7% accuracy which is higher.
Normally, for 1000 images it takes 8 hours and they pay us $0.80 depends. You can withdraw the amount only if you have minimum $3 in your account as balance thru paypal and this paypal deducts 2% to 10%. Also, i'm not sure whether they will pay the users at the end as because they can bann the account at any time.