Smyths have had the 10 pack for £10 for a while. Also avaliable in store and online, so no need to wait 1 or 2 months for delivery from Scamazon.
No. Usual pricing and better to get 2 for £15 as an example @ Argos.
Great product however Sainsbury's and Argos have 9 cars on a 2 for £15 deal at the moment. - https://www.argos.co.uk/product/9114629?clickSR=slp:term:hot%20wheels%202%20for%2015%20pounds%20on%20toys:1:351:1