As for PHP being faster than ASP, that COULD be true, but it's nothing at all noticeable.

ASP hosting is generally not more expensive than PHP, the company that hosts my webpage offers the same price to add PHP and/or ASP. (www.hostica.com)

PHP has a lot of built in functions for encrypting things, so it might be EASIER to keep things more secure... but ASP is fully capable of being just as secure.

hope this helps! in my own preference, I prefer PHP... just more like C++ and very very easy to pick up.