schools in Florida .. .some thoughts
I've been working in South Florida for over 2 years now and have some friends dealing with Heli Flight, Volar, Palm Beach, Pompano Helicopters etc.
Being a UK citizen you will need a J1 visa if you want to build time here in the US. Only Heli Flight can (could?) issue those but from what I've heared in the previous weeks they lost their ability to do so. Make 100% sure to check that they don't tell you bull**** if they say they can. I know of several students lined up waiting for their paper work because of that. Usually it takes only a few days for them to send you the paper work you have to take to the embassy after you wire them the fee.
Over all the most important part for you is to pick a good instructor... regardless which school.
I'm not a Schweizer fan but you also could consider Helicopter Adventures ... I'm sure you could get some info on those guys as well from someone here at the forum. They can issue the J1 visa as well.
You will hear good things and bad things about each place... looking back for me always important was to fly with a good instructor.