Nothing wrong with the 2012 Evo HM, its the same frame used for the current 2014 EVO HM.
Only thing is the Sram Red lacks the Yaw function of the current model.
$3100 isn't an out of this world deal, but not a bad one.

That frameset, used on ebay, goes for around $1500-2000.
Consider that u will get a set of $200 pedals with it, why not if you like that bike.

Is it worth $3100 new from a dealer, I think so, but it never hurts to try and bargain for more discount.