I feel that skis have performance floors and performance ceilings. A beginner ski has the lowest performance floor...anyone can ski it very soon after their first few minutes on snow. And the performance ceiling is very low. It just doesn't do the job an intermediate or better skier wants.
A race ski has a very high performance floor and the highest performance ceiling. If skied exactly right and with a very high energy input its performance is outstanding. Skied otherwise, it makes a skier worse.
So...you need to find a ski (and the size, 'cuz as they get longer they get stiffer) that suits your size, ability, and energy level. I'm a very good 6', 200# skier who uses the same model and size ski as smaller higher energy skiers I ski with.
Three rules to picking a ski to buy...demo, demo, demo. The difference between how otherwise similar skis feel on your feet is significant. One excellent, suitable ski will be OK and another will put a huge smile on your face--yet another might actually make you ski worse.
Peter Keelty's subscription web site, realskiers.com, costs $20 and has the best ski reviews I've seen. I feel that it is money very well spent--I subscribe. He'll also answer individual questions. It's easy to buy too much ski that is difficult to ski and sets your progress back. It's hard to find the right ski, but well worth the effort.