I was using wireless mouse/keyboard back in the days and it was crap. I had lag on my mouse, couldn't do any kind of basic photoshop work - the small lag was very annoying.
Now I just bought
this microsoft bluetooth mouse and keyboard and it works really well. I'm quite please with it, the lag is very very minimal and I can do my work in photoshop np. I had it for 2 weeks now and my battery indicator is over 90% and I use it daily for 10 hours-ish.