I have the KO2's on my Ford Transit van and before that had them with my truck and camper. LOVE the extra traction that they give you!! As for noise I am a VERY sensitive person to any noise in the vehicle and I can say the noise is not noticeable at any speed. At higher speed you have a louder engine and wind noises so the tires are not noticeable. Now maybe if I drove with windows open I would notice but I don't.
As for 4x4 vs 2x4. If the roads are that bad in the middle of nowhere you probably do not want to be traveling them. Take recovery gear and slow down. Like my Dad always said 4x4 is for the rich uneducated driver, two wheel drive will get you there if you use your head.