I prefer a UHC filter to an OIII filter. I have both and rarely use the OIII.
It blocks out too much light in my opinion.
The cloudynights.com list is better than any comparison I can give.
If you look under IIS, Images and Photography, Deep Sky, you will find a list of nebulae that respond to both a UHC filter and an OIII filter.
http://www.iceinspace.com.au/forum/s...ad.php?t=12896
It comes from the RCW catalogue.
http://cdsweb.u-strasbg.fr/viz-bin/V...source=VII/216