If using command R will that reinstall Yosemite cleanly?

Hi all. It appears that when I upgraded from the beta to the full system, I'm thinking there isn't quite a full install. The reason I say this, is because in the dock, is still the feedback assistant and I'm pretty sure that's not in the full version. My question is simple. If i use command R, I have already backed up to an enternal Hd, will that give me a fresh clean copy of Yosemite? I don't have anything else such as a USB thumb drive to boot to, so any help woudl be fabulous. also no discs to burn to either. Thanks so much.