I'm also unemployed (so I'm not answering your question from the point of view of, say, a well-paid city banker). However, I don't believe in the NMW. Similarly, I don't believe in most so-called 'employment rights'.
I believe that all employers should have the right to 'hire and fire' at will (unless they've signed a contract to the contrary). Further, they should have the absolute right to determine what they pay. For example, someone might currently be working on a supermarket checkout for �5.73 per hour (having worked there for, say, over 20 years). The employer should have the right to say "There are plenty of unemployed people who'll take your job for �3 an hour. From now on, that's what we're paying you. Take it or leave it". The employee should have then have 5 minutes to accept the offer or be instantly dismissed, with no rights to any compensation.
Businesses are there to maximise their profits. The law should encourage them to do so. Any employer who has the slightest consideration for his employee's welfare or ridiculous, so-called 'rights' should not be in business.
Chris