Hey!
I recently bought a cheapo XCSource ND1000 filter to shoot at daytime. With a price of 9$ it's does a good job if the exposure isn't over 20sec. Anything over that and the quality suffers a lot. The most extreme example here is a 6min exposure at f/32.
*Also, all pictures are taken on a cheapo chinese tripod which I got from an friend for a pack of potato chips. The tripod broke on it's first field trip :D
The Moral of the story = don't waste money on cheap things.