What I fear...My history of running..Will my knees suffer from the damage inflicted and interfere with my cycling...Knee replacement scares the hell out of me...Had to do it all over again, I would have gotten into cyling from the start...
Possibly, tread mills might be easier on the joints. Less jarring on the knees...I lived in cold climates, I think I would grow to like my trainer...Plus, swimming in the winter.