Ok girls

I posted a thread a few days ago about fitted over flat.
I think my arm is being twisted, and I want to give them a go. But if I do I want to get some decent ones that will last. So I have a couple of questions for you.

1) What are the best type to buy
2) Where do I buy them from
3) Do you need to buy "boosters" for night use
4) How long do they last
5) Do they come in different sizes

Thanks
Clare