Is the cross trainer or the elliptical trainer more effective?

What is the difference between a cross trainer and a elliptical trainer?

Do I need to maintain the ergometer? Do the moving parts inside wear out?

What can I train with a rowing machine?

What is the difference between an exercise bike and ergometer?

What is the difference between an ergometer and a recumbent ergometer?

How should I maintain my cross trainer?

3869 Ab&Back Trainer

3602 Cardio Strider 3.1

3603 Cross Rower 2.5

Can the ergometers be moved? Are the devices heavy?

3582 Dual Biceps Triceps

4131 Cross Stepper

4131 Cross Stepper

3602 Cardio Strider 3.1 - Handle Adjustment