I think there's not much to choose between Heli-Air and Cabair or any other -air, and even if there's a few pounds in it, go where you feel comfortable and they treat you well. Be demanding. You're the paying customer. Never pay a penny piece for anything up front, and if you don't like what you're getting, go somewhere else.
As stated above, get a medical first. I knew of a student who, despite urging, flew 17 hours before getting a medical, only to find she was diabetic. And yes, fly several hours before making a decision. Don't burn any bridges in the first flush of excitement.
Above all, know what you're getting yourself into. You'll pay a hell of a lot of money and work like crazy for years to get into a profession which offers little security, and even if you are moderately successful in it you will never be paid more than average wages. You've got to know you're going to love it for the whole of your life, because training for aviation means not training for anything else.
If you have the slightest doubt, go and be a lawyer or a doctor or an orthodontist or start a good business, then buy a helicopter and pay some mug to fly it around for you.