[pmyteh]

We have a Supreme Court. It's the old House of Lords judicial committee with new robes, though: the powers are nearly identical and the legal business of the HoL has been done by the most senior judges since the 19th Century.

The nuance here is that many Acts do not set out a whole scheme: they allow government to make subordinate regulations with the force of law. The Acts are (essentially, kinda) immune from judicial review, but the implementing statutory instruments aren't. (They haven't had full parliamentary scrutiny and are in practice just executive instruments - so can be struck down without parliamentary sovereignty problems as ultra vires the government).