Best way, just do it as you've done today and drop it without any notification. It's the best way combined with the voucher code, it won't surprise me if more retailers start doing this though i know of none that are actually selling anything near MSRP right now unlike ocuk has done... TWICE now so well done guys.
This is our third deal, first was an overclocked 3060 at £359 (£600 elsewhere), then Fighter at £449 (£600 elsewhere) and then this one today which is £650-800 elsewhere.