They're both incredible. You're missing out on two incredible experiences. There are very few games I'd pay full price for, but these two are it. And Rez too for shear fun factor, but you didn't say anything about it.
*Edit.. I thought the post was should I get these games, not get rid of em. I'd say keep them now, since trade in values have plummeted.
Blame the lack of sleep and being an overworked slave for corporate America