It is cheaper than the deal advertised last week which was 5% off. Also you get Quidco and Topcashback on this. So possibly £151 or £152 would be the net price.
paying by credit card would give you more protection (sec75 etc) in addition to the 12 months warranty offered by the seller.
You may prefer to buy costlier VERY GOOD CONDITION phones as few comments on previous thread complained about the phones from this seller being hit and miss for their GOOD CONDITION phones.
IMHO... The £25 off offer makes their Very Good Condition phones more competitively priced. that's what I ordered.