I'll give it 2 for the action but that's as generous as I can be.
I'm not an expert on the SAS but this was about the most ridiculous representation of them I've ever seen. There are no women in.the SAS. They don't arrest people - they are soldiers and not cops. The depiction of Hereford barracks is ridiculous. It looked like a cross between a call center and a NASA control room. And I'm pretty sure the head of the SAS doesn't show up in the PM's office wearing in uniform (he'd report to the MOD) or hire mercenaries to murder entire villages in former Soviet Republics.
A better SAS movie is "Who Dares Wins" with Lewis Collins. It's a bit of an oldie now but I'd imagine a lot more realistic.