The super tech WW oils have been WPP down here all along , as they have a plant in Houson I believe. AZ I heard had the same sale , or similar, for the Tection Extra, so I think it is a Castrol promotion - unanounced. I hate that you don't know the real price of anything in AZ until you get up to the counter though. AZ = lousy service in my book these days, at least the one locally.
For the price I say try it, you may really like it, i would expect the price to be 7.50 to 8.00 a gal. normally . In fact i might just go pick some more up too, but i already have about 20 gal of 15w40 in stock as it is, mostly Delo. I would be interested in what blend you may try too.