Pop3 Edge Speed? Webpage Cache Questions?

I don't have the iPhone yet due to a few worries....

1. If on EDGE, how is the speed of getting emails (pop3)? Is it as slow as loading say a webpage? Is it painful or not? I wish there were some benchmark tests somewhere. If anyone knows where I can find this, much appreciated.

2. I'm confused on how the webpage/safari cache works. If one loads say 3 websites (3 different 'pages') before one leaves the house.... can one pull up those pages later fairly instantly via cache? AND, if say, one has these webpages loaded via the pages - and one hits the button to check weather, can one just hit the safari button to go back to those already loaded pages? Or does hitting the home button wipe them out?

Thank you!