From a rotary perspective, a US FAA CPL(H) is pretty useless in Europe; you would have to convert to JAA so you need to look at the conversion process. There are some schools in US which do JAA licences but not IR; that has to be done in JAA airspece. And it ain't cheap. As a rough guide, in Europe, a helicopter flight hour is at least double, if not three times that of fixed wing.
Helicopter pilots are generally not paid as well as fixed wing and there are fewer openings for low-houred pilots. Helicopter instructors though, are paid more than fixed wing instructors but, again, there are very few openings in Europe at the moment.
You don't need to fly fixed wing before you fly helicopters and flying both will not make you any more employable. If you're thinking that learning fixed wing and converting across to rotary, you will need to budget the costs carefully in order to see if it's cheaper; unlikely in Europe.
As for lifestyle, it would depend on the helicopter role, but a lot of helicopter pilots do get to sleep in their own bed at night unless they are working foreign contracts which would typically be four weeks on/four weeks off.
Hope that helps.
Cheers
Whirls
PS - mostly written from a UK perspective from someone who have never flown a fixed wing aircraft.
