Wrapping up my 2 weeks on the loaner tour with the TWS 600, and here are my final thoughts:
Pros:
Connection quality - I didn't lose connection once over the two weeks I had them. The buds did desynchronize at one point, but that was a quick and easy fix. Walked around my open office space frequently at work and never ran into choppy connection or interference once.
Case - Just threw it in my bag and didn't think about it. They required a charge once a week over the two week loaner period and the case never unexpectedly opened. Loved the heft of the case too as I dropped it on my desk and didn't have to worry about it moving.
Battery - Beats some TWS, falls behind others, but I found that I never actually ran them down. I was doubting this at first, but I'm glad to know that others in the 3-5 hour range will suit me just fine
Fit: Where others had complaints, I didn't find any issue with the fit, fortunately.
Cons:
Sound: I'm not sure if it was just the set I received, but everything sounded extremely veiled. It was as though somebody had placed a blanket over the driver.
Bass: I can normally forgive a headphone for being bass-light...but there is just no bass.
Overall impressions:
Coming in to this loaner tour, I was really just looking to test more of the options out there. The Sony WF-X1000M3 didn't wow me and the bose soundsport reminded me of just about any $50 earbud sound-wise. I was really hoping that Hifiman would finally be delivering audiophile quality sound in this emerging market. To say I was underwhelmed may be an understatement. I don't know if I had my hopes up extremely high for these and they failed to live up, or if I'm just expecting too much out of the power delivery the TWS market is able to deliver. Overall, setup was a breeze. Paired with my Fiio M11 and OnePlus 6T with no issues and didn't drop connection the entire time I had them. I made a few calls and the microphones sounded fine to each of the call recipients, so no complaints on that front. The issue comes when going to listen to music which is where I feel a majority of people are going to be looking toward this set. A couple of notes from some notable tracks:
"Renegade" by Styx: The intro for this track is notable for the ominous vocals over pumping bass leading into the extremely energetic first verse. The vocals sounded alright, if a little veiled, but when I was sitting waiting for the bass drum, there was nothing....and I couldn't EQ these enough to make it present either. This isn't normally one of my testing tracks, but I spent my entire first day on shuffle and it was the first track to pop up. I tested with this track toward the end of the loaner period again to confirm it wasn't just an issue of break-in (HifiMan suggests 20 hours of break-in and I listened for around 60 hours total in my time with them) and there was no improvement.
"Don't Gotta Work It Out" by Fitz and The Tantrums: This song has an authoritative honking tenor sax throughout the intro and chorus. It's one of my favorite tracks for highlighting the lower end of the mid-range. The tenor sax really just didn't have any punch and was heavily drowned out by the vocals.
"Problem" by Ariana Grande: Ariana's not one of my preferred artists, but she has a vocal run leading into the chorus in this track that runs from the middle to the top of her mid range and leads to one of the absolute best bass drops in pop music this decade. On this set, her run is fantastic, and when you expect the bass, it just doesn't show up.
"The Raiders March" by John Williams: Telling that this would not suit much pop/rock with the lack of bass, I decided to test with some film soundtracks. This being one of the most notable themes of the 20th Century seemed like a fitting track. Again, bass is just barely present throughout, but the horn section does sound very good on this driver.
After extended listening, again, I don't think I can recommend this set as currently tuned. Everybody has their preferred sound, but I had friends and family test as well, and nobody could listen to more than a couple of tracks before they had moved back to their preferred earbuds or airpods. Hopefully a future revision can bring forward a better tuning, because other than that, I was extremely pleased with the package. Accessories were fine (Though I did find that my preferred tips improved sound ever so slightly over any of the packaged tips) and build quality was fantastic.
I would like to thank HifiMan for the opportunity to test on the loaner tour and communicating well running up to the process.