Brand new, Salomon foam cores might have the same flex and maybe even better than wood core skis. However, I feel I need to voice my personal experience in terms of how the ski degrades as compared to a wood core. My 1080's lasted two fine and glorious seasons of reckless skiing. However, unlike other wood core skis I've used, when a foam core loses its pop, its fucking gone. My skis definitely went through a transformation, and while they were kinda chattery to start with, they are beyond control on small bumps. Chattery as shit. I feel that this is soley due to the cores being compressed, and unlike wood, which stops degrading and can at least absorb some of the energy, foam just transfers it when it collapses.
Now, I'm not a industry rep, and I have not cut apart skis and tested them endlessly like I'm sure companies do. However, as stated, in my experience, foam is far worse that wood when its compacted.