PC on Ectos and Z-keys

I've been gone for a while, and I've had a pretty large stash of these two.

Which should i sell off and invest in?

I'm looking to hold my fortunes in one of the two items, so could anyone direct me to about how much each sell?

Thanks in advance.

Ectos = 4.5-4.8k
Zkeys = 5.0-5.5k

ectos staying pretty constant recently, 5.5 k by trader...so they mostly go 100k=21e (4.75 k), somethimes 100k=20e (5 k)... so range 4.7-5k
z-keys rised up a bit recently, 5-5.3 k each