It's easy to choose a plane but it seems to be not so easy to explain why that plane.
I would like to know the real differences between the planes you refer but the only thing I read is about beauty or about engines that are bigger or smaller
Beauty or nice colours don't saves money, what saves money is fuel comsumption, maintenance, load factor, ticket prices, airport taxes, ground handling, routes taxes, slots taxes, employes payments, to be better than competition, new ideas, etc, etc.
I don't know what plane would I choose. I like both the 737 and A320 and I'm not an expert on this matter.
Maybe this will begin another "hot" discussion (as I like) but I don't care, It's what I think.