Yes...Usually when I go out, mud is involved. I don't have a lot of places (atv parks) close to where I am...just a couple within a hour drive and they're nothing special, so me a a few guys ride on private property and we always seem to find mud.
To be honest, I never really have to get on the brakes that hard to notice. However, a few weeks back, a friend wanted to do some time trials on, his 800 rzr against my Z800. On three passes, I got on the brakes hard because there was not a lot of room past finish line. Front end did dip. But again, I've driven a couple different rzrs and our z800s don't come close to the stopping power they have. Those noses WILL dip...Never been a fan of the brakes since I picked them up.
Still think I need to change out the brake fluid...but I've never done it or had to bleed brakes before.