If it's something you gotta have, buy it as soon as possible. They'll never be cheaper. In my opinion, I think the mini is cool but not worth the price. I've shot one and prefer the slower cyclic rate of the full size. As others have said before, buy what your heart tells you. This idea works for me. If not, you'll just end up buying it later. You might as well buy the guns in order of "must haves." But, keep in mind, if you come across a good deal on a cool weapon it may throw your priorities out the window.
Dan