I have used the rubber bushings on my hi-hats for a while now. While there's no real difference in sound, I find that they help to keep the top hat steady but flex when it's struck, meaning I don't have to have the clutch so loose that it's in danger of vibrating apart. (And now I'm using one with a drumkey catch anyways).
I noticed in the picture that it looks like you have the wider end of the bushing against the cymbal. I have mine so that the narrower end is against the cymbal (less touching the cymbal is better in my book).
I have never used the rubber hi-hat seat, though. I personally don't think that is going to make a lot of difference unless you're someone who splashes the hats with your foot a lot, and even then a blind A/B comparison probably wouldn't be able to discern the difference.