silly merckx aside, i would rather have an eccentric bottom bracket than track ends on a bike set up with a rear brake. i am a perfectionist when it comes to setting pad height and toe in. i want to set them and leave them.

i think the best answer is semi horizontal dropouts. this allows you to make wheel changes without touching your brakes.

if i were building a bike with a rear disc than an eccentric bb would be a very viable option.