We bought two recently and following some research and advice we decided on half face rather than full - due to:
1. Full face obscures vision when lifted
2. Full face can get steamed up
No idea how true the above are - but the half face performs fine, doesn't steam up and still keeps us dry
They are cracking helmets, really pleased and we purchased ours through Malthouse - good price and quick delivery from within the UK so no worries re Import Duty.
Good luck - the hardest part was choosing the colour!!!