To answer your question: yes coreUPT is legit.
I might be a little biased, but they definitely make some of the best quality/price skis out there!
You should really consider looking at this years skis, they are on point (I have the TJ Pro and absolutely love it)! As for the bindings (DLD15), they are still very good for the price, but I personally don't like them as much as my jesters or sth16s.
If you have any questions don't hesitate to pm me and if you'd like a little promo code if you purchase something, just let me know.