Longer battery life is a big selling point for some, but i charge my S3 nightly.
£229 is still a really good price. Difference between the Gear 3 and new watch are negligible
This https://www.hotukdeals.com/deals/samsung-galaxy-watch-pre-order-46mm-299-42mm-279-samsung-preorder-before-6th-sept-get-a-free-wireless-charger-duo-worth-89-3009163 £50 more for the 42mm - you get a newer model plus a free charger.
Think the new watch is a better deal with the free charger and longer battery life