You lot are quick off the mark!
Thank You all.
As an O2 top - up seems to take 'a few tries', I'll stick to topping up online after all I think!
Keep it simple, and all that.
Great to know that an O2 voucher can be used in the future.
I can definitely convert the £10 O2 top - up, into a Giff Gaff goodybag yes?