CK10 is very good. Similar to DBA-02, perhaps a touch more analytical up top but with better bass extension. I think the DBA had slightly better imaging and sense of dynamics while the CK10 was a little flatter in both dynamics and soundstage. Treble specifics and tidbits will vary based on fit and tips. DBA has great integration as it only has two drivers, the CK10 has no crossover network at all. Joker and myself did a couple of posts a few years back (perhaps in his thread?) about the differences between the CK10 and DBA-02. We both liked them for different reasons. He preferred CK10, I preferred the DBA.
Joker was always someone I could understand how and what he was hearing and we completely got where each other was coming from. Always appreciated that about him.
OJ, CK10 is nothing like the ATH-CKM500. Both are better than the ER4S imho. That single BA they use is simply being asked to do too much. It's just too obvious once you hear it struggle against something like the UERM, UE4, DBA02, CK10. The FAD BA-SS is about as good as I've heard a single BA but the price is difficult to justify.