Hi BBear,
having spent some time in the same dilemma, I would certainly recommend renewing your IR/MEP on an aircraft - the cheapest that I found was at Elstree airport (not too far from Oxford) and the examiner was very fair and good value for money. He also organised the aircraft.
In total the renewal came to about £500 (including the aircraft hire and exam fees). Its not fair to post the examiners name here, but I have his contact details. If you want them, drop me an email.
Cheers
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