For your second question, it would depend on the ability that the Power Stunt or Extra is giving you. You'll really have to make your own call there.
and, if you get the errata (which i believe can be found in the Gimmick's Gadgets are of this site) Amazing Save, as well as all the Super Abilities (and possibly a few other continues powers) have been made permanent
H.E.R.O.I.C. Member of the 2nd Rank
Owner of a map to Paradise Island
"See this med-pack? See this gun? These mean the only people dying here today are the ones I kill!" -Field Medic, Cyberpunk Card Game