I went down the gas route and not the plumbing, via one of the commercial colleges. I did it like that as I could earn decent money straight away, I needed to, mortgages, car loans etc dont pay themselves. Id love to have an NVQ 2 in plumbing to supplement my Gas qualifications however, to the point of considering enrolling in college now to do it in retrospect. I think if you have the money and can afford it from a lifestyle/commitments point of view you should look at the plumbing first. I didnt and I do kind of regret it, Im doing well at the Gas though so it can be done if thats what your mind is set on.