Go back to 0.98.1, it's more reliable for many. Most people abandonded 0.99 as a lame duck.
98.1 beta seems to be the best in my book.. I run that on both of my 5 board Neptunes (or whatever we want to call them)
the newer cgminers are starting to have better features though, so hopefully we will be able to take those and run them on 98.1 beta (unless there are some new files in .99 that I needs that I am not aware of)
any idea where i can download the 0.98.1 beta firmware?
EDIT: never mind, sorry - i see the link now one page back!