Well you have to take care of it for sure - remember the screen is made from thin glass! But I've dropped mine (whilst not in a case - I hate cases!) a couple times and no bother. The back has a few scratches but the screens still fine. Just don't get it wet FFS!

As for PUSH - as far as I know, only MobileMe, Exchange and Yahoo Mail support push on the iPhone. Gmail won't as Google want you to buy their G1 phone (which incidentally DOES support gmail push). But I have mine fetch every 15mins and whilst at work thats plenty adequate as I'm busy doing other things anyway. And anytime you wanna check all you need do it tap the Mail App and it checks straightaway.

As for price - no idea if the PAYG are coming down, but I doubt you'll get any negotiation on price. They never have before, doubt they will now.