Some suggest not to use an ISPs e-mail address/web-space as it acts as an inertia hold to the ISP.
If, God forbid, O2 LLU becomes bad then it's much easier to migrate if you are not dependent on its e-mail address/web-space.
I recommend getting your own domain. Most providers will include email hosting in the price and it gives you a lot more flexibility. I get almost no spam and when I do get some I know the source and can block it and/or complain to them.
I use normal POP3/SMTP but tell my email client to leave on the server for 30 days as well. Used to be Purple Cloud, now moved to Tsohost.
I've gone back to running my own mail server. I bought a Fit-PC2 ( http://www.fit-pc.com/web/ ) and it acts as my media and mail server while consuming less than 4w.