Capstone seems difficult to justify at that price. It's possible that it will prove strong when built around, but realistically most decks don't seem to run enough redundant copies of installable cards to justify it. My Shaper decks could certainly ditch their extra copies of Kati Jones, Professional Contacts, and consoles (and sometimes throw away extra Plascretes as well), but is it worth spending 2 credits, a click, and a card to do this?
Ironically, the faction that probably wants Capstone most is Anarch, but the influence seems prohibitive, especially given that hardware tutors don't exist. The effect even feels kinda Anarch!
Panic Button is cool as, well, a panic button. I'm not sure it's generally useful enough to justify a card slot, though, especially given the vulnerability it adds to R&D. One cool thing for FA decks is that it draws the cards on the opponent's turn, meaning that if you draw agendas that you need to escape a lock you can still score them on your next turn.
All in all, I could see hammering the panic button being a good play in several situations-- I'm just worried that it's not worth the card slot and low trash cost in R&D.