i can't dissagree with Roger but i would recommend you take the 122. There is nothing wrong with extra volume especially in transition and the futura's have a big sailrange with a relatively good overlap so the 122 is a very nice choice if you're sailing 6.0 and bigger (you said you were sailing medium winds and i assume those are most frequent at your spot then). as you progress, like roger mentioned you may want to start looking at 7.0's or even 7.5s which'll sail a lot easier on a 122 then on a 111 especially at first. When i sail 113 L with a 7.6 it's far from a easy to get out of the water because of a) my weight which is about 15 k more than urs, but also because, of the amount of water that the sail takes making it a lot heavier, even after 'draining' the water out of the sleeve and stuff.
And then there are all the afore mentioned factors that Roger wrote earlier.
hope you clear things out soon
Haiko, AKA crazychemical