I've only given Luna 3-4 kibble bits to try - we're still finishing our big bag of EVO before making the switch again (EVO is great, but hooooey, the litter box smells! I hope Orijen is better in that dept.)
On the few bits she's had (twice), she sniffed, explored it, and when I broke one apart for her (she's a very thorough sniffer) she ate them up.
There's hope!