Just ordered 4 Litres of Castrol Power 1 Racing 4T 10W-50 fully synthetic engine oil from OPIE Oils.
I started with the Moto-Oil.co.uk website price, & OPIE came out slightly cheaper at £10.83 per litre with free P&P.
Yes, ebay may be cheaper again but I don't use it & OPIE won't accept any auction sites or third party merchants, an example being Amazon for their "Price Beater Promise".
OPIE say, "Goods sold on auction web sites or by third party merchants are frequently grey imports or old stock.
All our stock comes either direct from the manufacturer or from the official UK importers for products manufactured overseas."
A "Google" search has come up with Engine Oil Direct,
http://www.engineoildirect.co.uk/shop/4 ... 4l/7926474,
might be worth using their price for the OPIE "Price Beater Promise" next time.