I think, as far as the bike goes, frame geometry and type of tubing is the most important aspect of cycling . This is , of course assuming the bike is in good tune and well maintained . The other factor , tires , and the correct pressure can have a huge effect . I ride old steel racers not because I race. I ride them because I am long legged and short trunked , so the geometry is most comfortable . Of my bikes , the Columbus tubed bikes seem just a bit stiffer and more responsive than the Reynolds tubed bikes. That said , they are all very comfortable to me and my build. I am 6.' and about 155lbs with a 35" inseam and these early racers are perfect. Even at 65 years old , I can ride these bikes easily although I swear the hills are getting steeper! Joe joesvintageroadbikes.wordpress