Dont need to use it at present so not a problem but I have heard that they are very quick to call the ICB if you miss a payment, not sure how true that is.
I put my head down, move as far left as i can and walk as fast as i can to pass them.
If you can stop yourself frm not using it unless you need to then it's ok to keep it. I couldn't do that which is why i have a very small limit and requested that they never up the limit!!
You can defo keep the old one active when you move you balance to another credit card, I moved my balance from BOI to Tesco an still have both cards, I was also thinking about MBNA but I dont think i will go with them now, I heard they are very handy at adding up the intrest