Not I, but that doesn't stop me buying new stuff I have nowhere to display.
I actually have to speed up my opening of toys so I can throw away the boxes to make space for the newer incoming ones.
What's wrong with having a large part of your collection in storage? I only have limited display space and cycle toys around from time to time, just like every art collection/museum in the world.
One of these days we'll hopefully move from an apartment to a house and I'll have more room but I doubt I'll be able to display my entire collection still.
Do I need another MP Prime, not really. I love MP-01/04 and still have a version of each. I also have the Hasbro release of MP-10. At the time I thought the Takara price was insane unjustifiable. Like others here I'm not even sure MP-10 is the better toy. It has some better features but MP-01/04 is still outstanding to this day.
I kind of wish they had stayed using the MP-01/04 'scale' through to now and beyond. I have enjoyed pretty much every MP release, I don't know if the 'more animation accurate' direction the line has taken of late is the way to go. I do like the more griebly look of the earlier 'teen' Masterpiece toys.
Will I get another MP Optimus prime if they do it, probably. But I doubt I'll jump on the pre-order like I did for most other Masterpiece toys I have.