People have to know what you are asking, before they can answer your questions.

Even if some one gives a "best" answer about an exercise, it's only the "best" answer for single specific situation, which often does not apply to many people.

The best exercise for you, using a gym, or a bicycle, is the exercise that isolates and stresses that muscles that limit your performance. As Clint Eastwood used to say: "A man's got to know his limitations."

Without an evaluation of your needs and goals, I'd have to say: "Do you feel lucky? Well do you punk?" "'Cause you're gettin' nothing but a barrel full Bool Chit - so far."