I use P2, have for a long time now. Don't even remember what working with tape was like anymore. But there are two huge issues with any tapless format, be it P2, SxS, Ki Pro, or anything else.
First, have two copies of everything you shoot. They're digital files, and digital files, once put on a hard drive, can become corrupt. So you want back-up copies. Tape is way more stable and reliable than digital files on a hard drive, in the long run. Although neither is 100% bullet proof.
Second is archiving. Hard drives sitting on a shelf in a closet doing nothing A- loose electrical charges over time, thus data becomes "weak" and can become corrupt, B- can freeze up and not boot when you plug them back into a computer. Remember, hard drives are mechanical, analog devices, and are pron to all sorts of problems running in a computer, or sitting silently on a shelf.
Blu Ray DVDs are a bad solution, as they are more pron to physical damage than hard drives, are expensive, and 50GB is nothing when you're talking about video files, especially HD video files. They take forever to burn, too. And you'll use a ton of them to archive any serious film project's digital footage.
The best archive method today is DLT tape, LTO being the most popular. But these are not cheap solutions. They take some bucks. You're looking at $6k minimum for hardware and software to build a realistic solution.
Thus, the tapless workflow is GREAT when used responsibly. But the camera makers are taking no responsibility for digital file reliablility, nor for archiving issues. We're all on our own to figure those two MAJOR issues out. Larry Jordan on his Digital Production BuZZ radio show/podcast, and in his writings (free monthly news letter, every filmmaker should be getting it), talks extensively about these issues.
