The FAA Rotorcraft Licence allows you to fly rotorcraft under 12,500 lbs (excluding Robinsons for which there is I believe some type rating). In theory you can fly any machine IF you can convince the owner to give you the keys.
In practice, and my limited experience, it won't happen without some sort of checkride...or if turbine, 'initial turbine course' and then you will then need a minimum number of hours to solo in the aircraft for insurance purposes.
Also of note re: insurance, is you may be required to take out renters insurance or if insurance is included it may not include the hull! Bend it, it comes out of your pocket.
What the FAA license does (and one reason I opted for FAA) is remove the requirement to be tested on each type you fly every year - potentially very expensive on the CAA system if you are a professional pilot and hold multiple type ratings. On the US system you need to remain currenta nd satisfy the BFR requirement.
The FAA system has some flaws, but is light years better than the Campaign Against Aviation
