Interesting post by DennisK above.
I passed my PPL(H) after 45.1 (i.e. test at 45.1 hours), so it can be done. This was in a R22, with no previous experience.
I did the trial lesson, to meet the instructor and get an idea from them what they thought of me. At that point I got the medical out of the way before starting spending money. I would tell anyone to do the same, if you don't click with any instructor you will have trouble.
Looking back at my logbook, it took just under a year in all. I had a wait to do my QXC because of the weather. I tried to do one to two hours a week, with a few gaps because of work commitments.
I have to say, it is probably the best thing I have ever done, despite the cost.