Thanks for you replies, guys.
In that case I think I will wait until the lens is out for the masses and not be an early adaptor. Most of the films i take / create are when I am with my friends, when I am on some kind of leisure activities, etc... So typical scenarios where there is a small window time-wise to take the shot. In most of the cases, being quick is what really matters and I would hate myself if I dont got some unique moments because I did not master the skill taking films with such a setup.
So, wait & practice is what is most important.