I think this is stupid in the extreme, and you SHOULD NOT do this ever.
Bitcoin is super interesting as an asset vehicle, but I would not put all my eggs in that basket. For as much as I might not like the Fed and some of the monetary policy it makes, it still gets things done. Right now bitcoin can't seem to change the block size, it needs to, and a squabble could cause serious devaluation of the product as a whole.
There is also the ticking time bomb of the satoshi coins. Right now one individual (or group) controls something like 6% of all the coins available, and on a whim, could cause a major devaluation over night.
All this having been said would I consider buying and holding some bitcoin as very LIQUID asset, and cash equivalent. I sure would. How much would I put into it, no more than a few grand honestly, a sum I am willing to loose.