Here to start the discussion which is better? We have heard the threading problems with some on the Polar Pro, but at only 2 grams difference can be mounted with no counter balance. The SRP filter comes in at an additional 7 grams, so counter balance may be recommended. The gimbal itself is not perfectly balanced from factory and that may be a intended design purpose or result of which we do not know of? So balancing to stay in place in any position when off may not exactly be the right balance. I know mine stock falls to the side and forward, but yet in flight is perfectly level, no gimbal adjustment needed from factory. So lets start a thread comparing the results of each of these and try to determine - which is better overall? Which has better optics? Which has less impact on the gimbal? What you see here was almost evenly priced...the Polar Pro you get 3 at 69.99 and the SRP was like 54.00 but is a dual ND8 and CP.