Zotac AMP! or AMP! Extreme? Any difference when OC?

Hey guys, simple question and sorry to bring it up so much.

About to build my 1080 Ti build and have heard great things about Zotac, AMP! For $700 and AMP! Extreme for $770.

I plan to mine ZEC with heavy OC, and heard they both have the same OC capabilities and reach about the same speeds and values, but not sure since I haven't found much about them. I'd hate to throw +$70 per card for same results.

Any other recommendations are welcome. Thanks!

1070 AMP is way better return per dollar than 1080 *, see https://bitcointalk.org/index.php?topic=1733240.msg18421733;topicseen#msg18421733

You think? I was researching and doing some calculations, and 1080 Ti seems the best for ZEC. Will look into it a bit more before buying

Card,Cost per,Sols per,Watts per,Card Count,Cost,Sols,PE per,PE (for card count)
zotac 1080 ti,$759,660,125,2,$1598,1320,5.28,5.28
zotac 1070 amp,$394,437,120,3,$1182,1311,3.64,5.46

You might find this resource useful http://zcashbenchmarks.byethost16.com/?i=1.
Found the wiki but it wasn't the actual one I had in mind but still has a good list: https://en.wikibooks.org/wiki/ZCash_mining_GPU_Comparison