Here's my 2cents: I suspect that if you buy the Partner, you'll like it, especially if you don't have much space for reloading wherever you do it.
It also seems to be portable, so might be handy at the range if you wanted to do the shoot/think/load process on the spot and develop keeper loads.
However, given that you have a 280AI to feed, I think that in the long run you might be happier with the solid, precise characteristics of the Big Boss or the Rockchucker. From what I read, the round has a very long reach, so the more precise you can be with your loading process, likely the better end result.
Buy once, cry once.
I have a Redding T7 that I have have used to load a few thousand rounds of 223, 308 and 7mm08, and I have to say that I love the solid feel of my giant green mushroom.( If you see a pic of it, you'll know what I mean) It's a killer to lift though.
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