Signed up for Option 2 BT Broadband in October, which included 2mbsec download speed. Thought it a bit slow recently so used speedtest.ie to check and found I was only getting 1mbsec download speed. Called BT Tech support who said that although I was being charged for 2mb, they had only hooked me up for 1 mb, ergo I have been overcharged €100 over the past 6 months. This has been credited back, but had I not checked I would have continued to be fleeced.
Moral of the story is check that whatever download speed you have signed up to is actually what is provided...