Exercise Bikes vs Treadmills

I just bought an exercise bike. I think treadmills are better practice for running, and may be more challenging, but bikes have the following advantages:

• Safer - if you trip or faint or whatever on a bike, nothing's going to happen to you.
• Last longer / easier maintenance - I've seen so many treadmills with tangled belts / out of service. There are so many moving parts and a motor. I feel a bike would be easier to repair.
• Cheaper - comparing the same quality, of course
• Can be used to exercise leg muscles
• Multitasking - you can use a treadmill while watching TV, and maaybe reading. You can use a laptop, tablet, phone, while cycling. More convenient = more likely to exercise.
• Wider range of fitness/age - related to safer, even people with difficulty walking can cycle.