I dont think getting the £18K+ is the question. The question is is it likely to get a return in the end. I started flying late at the age of 33 and was v v lucky and now fly B737. I was on a large course going through training and many of the people, far younger than me still havn't got jobs.
If you look at some of my other posts I usualy advocate people to go for it, what have you got to loose. However unfortunatly at your age I feel you are going to be fighting a very long hard battle to get a job. You will be 46ish when you finish, and that is getting to old to find your first airline job.
If you look at the job market it is very poor at the moment and there is a large surplus of young qualified and in some cases type rated pilots that are ahead of you in the job que. The airlines look for hours comensurate with age. At 46 they generaly would expect you to be getting towards captaincy, not looking for a first job. When I applied for jobs originaly 99% wanted 1000 - 1500hours minimum. When you finish training you will have in the region of 500 based on your current hours. That is a lot of hours to get to be in with any chance at all and you unfortunatly, are getting older all the time.
If you want to be an instructor then I would say you have much more of a chance.
Saying that the other guys are wrong VFR and CPILOT is simply not true. They are being realistic, both of you are young PPLs, with little experience of finding an airline job. The other older guys with the success storys are generaly in mid 30s at the latest. You do not see all the horror stories on Prune remember that.
I have been there, seen it and bought the tee shirt with training as an older pilot. Think very carefully, if you want any more information email me.