It's been proven that the differences are incredibly small, and if you just learn how to pedal you don't need any expensive pedals and shoes that people try to make you feel like you need.

Whatever a person is currently using is what they will say is the best, otherwise they will feel like they've wasted their money. *Of course* when a person goes out and spends $100 on something they will "feel" a huge difference. Clipless might make some inexperienced cyclists feel like they are so much faster, but it's all in their head unless they have very poor technique.