Experience with ND filters; B+W, Singh Ray etc

[ArcticShooter]

I need some ND filters. Will use it for long exposure shots on falls and waves.

Have anybody tried the Singh-Ray, Vari-ND?
Vignetting on a 10-22mm? When does vignetting stop?

Otherwise I just get the B+W ND 110 (10 stops)

[Minty]

Oooh, spooky I was just about to post a very similar question, so very interested in any responses.

Are the cheap ones on Ebay worst than useless or worth a bash if you don't expect perfection.?

[ArcticShooter]

I bought the cheap ND filters for the p-holder from Ebay.
You can't stack them since the color will be totally off.
They work ok in single use.
But buy cokin or even better the Lee filters