I have several Bay I "Rollei" Brand filters for my Rolleicord Va.

Several questions . . .

1. Are the Rollei Brand filters quality and good for BW photography?

2. Are there better non-Rollei brand filters out there? Where can you get them?

3. What is the best way to clean Rollei filters w/ dust and hard to remove micro-debris?

4. I noticed on one of the filters (orange) -- there are tiny pinhole (no filter color, just clear transparency). Will this have any affect on the neg?