I think Mils are easier than MOA because everything is 1/10, but it really doesn't matter much. If all you buddy's are in mils or minutes it is a little easy to share wind calls. If you can learn to speak in values (like full / half value) or even better, actual mph it make the differences moot.
I would also recommend getting a reticle that is newer that a old fashion mil-dot. Get a First Focal plane scope! The one you listed is not 1st focal, that is why it is less cash. If you serious about long range (or you're wife is) make sure you get a FFP scope.
Burris XTR II 4-20x is a great scope, better than the 5-25x version. SCR reticle has 2/10ths mil marks which are great. The Gen2 mildot reticle is OK, I personally would only get the SCR.
If you want a Vortex I would wait for the Generation 2 PST. It should be much improved over the current models better zero-stop, glass, etc.
Bushnell DMR2 (or DMR / HDMR) is good scope in this class also. Not sure if it is within you're budget.
There are some other options out there too and more companies are getting in the game.
Feel free to PM and I would be happy to help or try to explain any of this stuff.