I ran a logitech keyboard and microsoft mouse for about 5 years on my main rigs.... no problems whatsoever.
Still running that logitech keyboard with an old PS/2 Intellimouse with my gentoo box... but for my main rig, I switched to a Saitek Gamers keyboard and a Razer Copperhead.
i have wireless logitech keyboard and wireless microsoft mouse, and its no problem unless the receivers are too close to each other. then they occasionally interfere. just put them on opposite sides of the monitor and all is good.