Came across this at Opie Oils when searching for premium grade oil. This stuff does retail at double the price usually and is amongst Opie Oils premium range. At a fiver more than Magnatec its a great deal but once you switch its generally not recommended to go back to lower grade oils so you'll be paying a premium from then on unless you get another good deal.
EDIT: The 29.99 price is availble if you sign up to one of the owners club forums (think it gives a 10% discount?), its free, just a little hassle to register.