I'll ride different bikes into work depending on my plans. SS EVO for days with club rides after work, my cyclocross rig for days where I am taking some "shortcuts" home, and have done the MTB when it snows.. I told my friend this morning that As long as we are vocal about what we want the ride to be that day I have no problem with tailoring the ride accordingly.. Now, at pace, we are likely very close in ability, but recovery days, different bikes, and weather can all make a difference. We will just come to an understanding and make it work..