Im trying to figure out why.
What is it that you want to hear? Multiple people have given you their reasons for preferring 870's (even the Express models), and others have stated why they prefer 500's... yet you continue to ask the same questions.
Some people prefer a steel receiver, some prefer an aluminum receiver.
Some people prefer the safety on the top of the receiver, some prefer it behind the trigger.
Some people don't mind the loose/rattly forend, some are bothered by it.
IT'S A MATTER OF OPINION!!!!!!!!!!!!!!!!!!!!
I'm anxiously awaiting the "If 870's are so great, why are there so many used ones for sale??" thread...