Quote Originally Posted by Adzma
but the question is what do I do with my Takara one if I do buy a new one?
You could sell it. But you might want to sell it before the Hasbro one is released - people won't be as willing to buy a Takara version after the Hasbro one comes out, and even if they are, they won't be willing to pay as much.

Quote Originally Posted by STL
My Takara one can go straight back to box for display.
If I were you I'd display one in robot mode and the other in jet mode. That's what I do with my two MP Starscreams - Takara version in jet mode and Hasbro version in robot mode. IMHO it looks better than displaying a Japanese MP in box since they have no windows from which to view the toy. Just my 2c.