Well, volume is very exact science from a physical standpoint, but when it comes to real sailing and schlogging, it becomes very personal wh one thinks it "enough". I'm 70 myself and for me the 70 is enough and it is EASILY my best all round board and whenever I can only take one board its always the 70 and I don't even think about taking the 75. With 5 kilos more you will have to struggle some more, but it should still be possible in everythng except the most tricky conditions (lots of current working against you, super, super light, really big, closing channel, onshore or all of the above in some nasty mix). But except for the sinking at standstill, the 70 is very effective and when power is on I think you will move around pretty much as good as on the 75. And once up to speed on a wave, the 70 has a lot more drive to is and you will definitely appeciate that on the good days at your spots (of which I've sailed Hanstholm and Klitmöller).
So, overall the 70 will be more allround and in context of your header "control in big waves", the 70 VERY good. But if you're still unsure about the schogging thing, the 75 is it and in you "normal" Denmark surf it will work excellent too. So, its all about choosing between some extra comfort for the light days or the extra drive and control the good days.
Last edited by Ola_H; 2nd October 2007 at 05:43 AM.