Any experience with bower lenses for S3 IS?

[nap]

Hi, has anyone here used bower lenses, specifically wide-angle and teleconverter lenses, for the S3 IS? How is it?

I'm asking because they're cheaper than raynox lenses. I found them here:
http://www.camerafilters.com/pages2/telephotoconversionlens2Pack.aspx

and here:
http://www.camerafilters.com/pages2/wideanglelens.aspx