Simoniz car shampoo 5L - instore @ Asda
Had quite a few in my local (Havant) + others reporting the same in various stores so seems like its nationwide
Not tried the stuff yet but seemed like good value.
"up to 300 washes" "cleans to a shine every time"
(The link is Wilkinson as I originally thought £5 was a good deal but seems not!)
Thanks for letting me know guys about the £1 offer