If none of this https://bitcoin.org/en/version-history concerns you, you should be good.
I was actually reading this and though well OP is fine, but then I didnt post that because I was not sure what OP actually wants to do.
For generating keys thats fine, but an offline wallet would also sign transactions. So the "Transaction malleability-related fixes" might be an issue. Esp. the tightening of "IsStandard()" might result in transactions that are not broadcasted across the network.
I know, sometimes there's so many options on what they don't post or want to do exactly. So I just post the info and let them make up their own mind. If there are more questions they always can come back.
In this case OP also could generate the keys in 0.8.6 and by the time he wants to spend he simply imports the wallet.dat in a (by that future time) current Bitcoin Core (as long as it's backward compatible).
But of course, IMHO, if there is a true offline computer to be involved, why not use Armory in the first place? The beauty of bitcoin: So many options
