Nurses are really in demand, so that's a pro. The NHS is badly underfunded and so nurses (along with most everyone else who doesn't work in finance, TBH) are underpaid, which is obviously a con. I'd say it depends on whether you think this would be a job you'd be happy to do for a long time, or if there is another job you could do with your current qualifications that would be as good or better. It's worth spending the money if you're dedicated to nursing, but if you're just looking for a job then there may be alternatives that suit your current skills.