there may be something to the base width this is from keeltys site,
The physics of 70mm skis on the groomed, where 80% of skiers use them 80% of the time, is surprisingly simple. 70mm waists come up on edge more slowly, and return to flat more rapidly, than do the 62 to 65mm skis that are the preferred tools of hard-snow technocrats. What this means is that they skid more easily and adapt better to traditional technique in which tips are pressured and the downhill ski is steered into the new turn. That's it, that's all.
But, it's a big all...
The effect of this behavior is that 70mm skis are more forgiving and easier to ski (remember, we're talking about the groomed here) and make skiing more fun than it otherwise would be for a big segment of the skiing population. And that, in turn, is mid-fats continue to be the best selling shape.
You take it from there. If skiing is something you do, rather than something you have to do, and barring certainly anatomical anomalies, chief among them extreme bowleggedness, and you spend most, if not all of the time roaming corduroy groomed, the this is the shape for you. As always, we urge everyone to try before buying, but if "leisure" describes your approach to skiing, 70mm skis are the ones to start with.