George Dobrescu posted an extensive review of the DK-3001 over on Head-Fi. From the review it sounds like a great 3BA/1dynamic driver IEM. Priced around $500, it is middle of the road for a quad-driver IEM.
Pros – Relaxed Signature, Smooth Sound, Strong Bass, Large Soundstage, Good Instrument Separation, Good Comfort, Large Number of Accessories Included, Useful Carrying Case, Great Value, Musical, Romantic, Natural
Cons – A tad too polite for metal music, The sound Might be too relaxed for some.
Review of DK-3001
HiFiChris has a review of the Titan 3 on Head-Fi. Included in the review is a comparison with the Titan 1 as well as Titan 5.
In summary, “Out of the Titan series, the Titan 3 is the most balanced sounding in-ear. It also has got a high resolution with a fast and punchy as well as arid bass and a convincing spatial presentation.
Here is actually really nothing to criticise from my side and the Titan 3 scores easy 5 out of 5 possible stars in my rating”
Review of the Titan 3
User Hisoundfi on Head-Fi posted a review of the DN-2000J IEM. His summary:
Pros: World class clarity, Speed and extension in both directions, Tons of accessories, Many options for a customized fit and sound
Cons: Can be bright and thin for some people (in stock form), Driver flex with installed bass rings