British equivalent of 'bang for your buck'

Solution 1:

Try get your money's worth

to get good value

Also try more bounce for the ounce or worth every penny, although not that British.

worth the entire amount that was paid for something.

Solution 2:

in Scotland they say "a bargain at twice the price", which doesn't have the punch of 'bang for the buck', but does have the advantage of lending itself to the ironic 'a bargain at half the price', which is often heard as well.

Solution 3:

Value for money:

• (British) Used in reference to something that is well worth the money spent on it: this camera is really good value for money

(ODO)