If your swapping cams, take the time and install new springs and all the other goodies that go along with it. Why take the valve covers off again? I have been talking to some folks about it becuase I want to swap my cams in the next month or so. It makes sense, so that's what I'll be doing.
With anything over a 500 lift you will need springs. Compcam springs will run you $179. I'm glad I bought mine. When I had my shotblock installed I only had SHM 2730 cams which didn't require springs but doing the right thing I replaced them anyway. I then swapped to VT stage 2s a month or so later