Awful - avoid at all costs.

I sent 2 ipads (ipad 4 & ipad mini) to RPC for recycling based on the cash offer (£388 for both) from a compare website.
I wiped both (and disconnected them from iCloud) and made sure I followed the instructions they gave so they would be acceptable.
It cost me £11 to send them safely to them.
A few days later I received an "urgent" email telling me my ipads had been revalued.
The ipad 4 had more marks than they expected - so they offered 1/2 the original offer...
The ipad mini supposedly hadn't been disconnected from iCloud - so they offered me £15!!!
The alternative was to pay £3 to have them returned to me - which obviously I did.
When they arrived, the first thing I did was switch on the mini and low and behold - it is completely wiped and not linked to an iCloud account. In other words, no justification whatsoever for reducing the offer.
The ipad 4 has got some marks on the corners, but it is in perfect working order.
I have just rung them to request they refund my postage costs (£11 + £3) and now I have to wait for someone to call me back.
Avoid at all costs.