If you do end up RMA'ing it be aware they only refund £12.50 of the postage, i sent mine back in the box it came in which cost £17.95 via royal mail only to be told they'll only refund £12.50 of it.
if it is faulty then ocuk HAVE to refund the FULL cost of delivery back to them(along with the full cost of the item including the delivery cost from ocuk to you), I'm not fully up with the legal stuff so can't quote you what particular 'act' and what not but I'm sure some one with better knowledge will post on here.
if you're returning it under the dsr then ocuk only refund the delivery cost you paid when you bought the item, you have to cover the delivery cost back to ocuk.