resistance bands - recommendation needed

morty1966

I have been looking at resistance bands on amazon but don't know how cheap to go. There are some for £10 ish and then into the £20 + bracket. Is it worth buying better quality ones or would a cheap set do? I am doing Jillian Michael's body revolution so would be using them most days.

Edit: I went for the cheaper ones in the end, based on my bank balance!