I have to agree with Shunka. Make two batches, one with pecans, one with walnuts. Taste, then decide. You don't need to make both at the same time. But, if you do, I'm sure all of us would gladly go to your place and help you taste-test
Personally, being from OK originally, I'd go for the pecans.
Peace, Love, and Vegetable Rights!
Eat Meat and Save the Plants!