I've made several purchases from ffordes over a number of years and can recommend them as an excellent company to deal with in terms of description of items and speed of delivery (I'm at the very opposite end of the UK from them).
I buy lots of lenses from ffordes, both new and secondhand. The lens descriptions - signs of use, obvious signs of use etc. on their website are pretty accurate. They are happy to give you a further description over the phone as well.
You have a week to return any lens anyway. I've always found them helpful and reliable.