7 could work for many years to come if you are vigilant about not updating any, and I mean ANY software. I still use it to access old projects but find it crashes more and more and more the harder it is pushed. For any real work I’ve moved on to Avid and Premiere CC. And just by way of tweaking the community, FCPX was never a consideration. Editing dialogue in FCPX is like trying to wrestle a bull to the ground by its balls. (They don’t like that.)
Tim