Sorry guys, but I'm a carbon junkie and know very little about aluminum arrows other than those were what I shot early on when I first started shooting wheels.
My question is:
Let's say we are talking about Easton Gamegetter XX75's vs. Easton Legacy XX75's.  Is a 2016 in the Gamegetter the same as a Legacy 2016 as far as spine goes?

Yes, both .531" spine.

Far as I know yes, the only real difference besides finish is temper. I think the Legecy are a higher temper? Which should mean they bend less.

Yup-- both are 10.6 grains/inch, .531" deflection @ 28" span.

Awesome!  thanks guys!

You will be happy with either as they are the same.

Another very similar is the xx75 Camo Hunter

One of the reasons I'm such a die hard fan of aluminum arrows are the consistency in spine and weight.  I have several dozen, some new, some 20 years old or more and I can pick up any of them and they group together.  I don't know how the several dozen that I have differ in tensile strength, they may be all the same for all I know, but I can't say that I'm able to tell a difference in durability. The discontinued Autumn Orange and wood grain classics are hands down the purdiest though.

XX75 is XX75 no matter what the name is that follows. Legacy, Camo Hunter, Platinum, etc are all made of XX75 material to the same tolerances.