Usage of "by far" and "far and away"

Hi,

I've almost come to think that there's no difference in usage between "by far" and "far and away" whatsoever, but there's still a shade of doubt in my mind about that )))

Could you tell me if you sense any difference between the two sentences in each of these two groups:

1.1. He is thought by far the most prominent roofer in town

1.2. He is thought far and away the most prominent roofer in town

2.1. The movie I saw yesterday is by far the best I've ever seen

2.2. The movie I saw yesterday is far and away the best I've ever seen

Thanks in advance !