I'd like to add my thoughts on a few of these, and For comparison; I own the following buds:
and the new guys:
The PK3's were my first set, and I appreciated the fit (the Yuin headphones are my favourite fit wise, with a small, subtle body which looks cheap but is intact quite nice and doesn't need foams for a comfortable fit int eh ear. I can sleep with the Yuin's in and wake up with no ear pain). The sound of the Pk3 however, is very mid bass oriented and isn't my favourite, however these are my main pair for anywhere outside of home because of the balance between SQ, Price and Ergonomics. The Yuin packaging is serviceable, with a plethora of foams and a 6.3mm adapter which is nice. The included case is a bit cramped and I'd recommend getting a larger one for both ease of use and the conner of damaging the headphones when putting them in.
The PK2's have a much nicer treble/mid sound to me, and essentially fill in the gaps i heard with the PK3's. However the jack wore out after a few months on my PK2's, so I had to solder on a new one, somewhat confusingly as the jack on the PK3's are still going strong. Whilst the PK2's perform better than the PK3's, unless you really like the warmth of the Yuin sound, I think hat the better value option is the MX471. Same case/packaging as the PK3's.
The Sennheiser MX471's are IMO the best value bud on the market right now. They sound clear, crisp and relatively uncoloured, yet posses a hint of warmth which I feel is lost on the higher end MX985's. However, the fit on these is rubbish. Ive tried the foams and they're marginally better, but in my experience the rubber 'donuts' are the best fit for these. The cord is another highlight, as it seems sturdy well made. However, I'm not a fan of the styling, which is a little on the tacky side. I bought mine for $27 AU though, cheaper than even the PK3's and with a Warranty which i might be able to easily use whilst speaking in English! The packaging on these is basic, a plastic blister pack with 2 sets of foams and one rubber donut - thing. The carry case included is a (faux?) leather though, and is a nice addition.
The Sennheiser MX985's are a mixed bag for me. I was excited to get my hands on these, as up until this point I was used to the sub $100 peasant class of earbud. The first impressions of these for me was merely "transparent". By all means these are the most accurate headphones I own, the bass, the mids and the especially the highs shine beautifully. Ive seen these described as "the BMW of the earbud world" and I think this description is apt. They look great, and sound great, but ergonomically were just mediocre for me. They fit my ear pretty well, but the rubber ring that goes around the outside of the speaker broke within 3 months and rendered the left bud scratchy and uncomfortable. Ive since sent them back for warranty, but the company i bought them from (Accessory Jack) is in HK and Im expecting at least another month before I get them back. IMO these headphones aren't high enough above the 471's to be the price of 5 of them.
The packaging on these is quite nice, and they include an aeroplane adapter and a bunch of foams/extra goodies. The carrying case is OK but I still prefer the basic clamshell you get with many Chinese buds.
Now, onto the new guys:
The Dasetn M1's are the most neatly packaged of the bunch, with the silver box and blue colour giving off an air of quality. This ends relatively quickly once you begin to use them. I found the sound to be mediocre, (similar to the PK3), with a slightly muffled (some may describe it was warm) sound which is mid oriented. These are overall alright, but not phenomenal buds. I found the fit to be mediocre, but improved to a decent level with foams. The sound as mentioned before is mid oriented, with a close, Yuin style soundstage and weak treble and bass response. Overall, useable for spares but not worthy of being a main set. I tried these with some piano oriented tracks (eg. Mika's "Grace Kelly", the piano came out crisp and the vocals are smooth. This track does shine on this set) and whilst the close soundstage and mids did work well with piano sound, I don't feel this is enough to redeem their other failings.
The Dasetn M760's are certainly better than the M1's, but still only marginally so. The soundstage is very similar, and the Mid oriented sound remains, however the treble on these cuts through slightly better and the cable (red) is nicer. However, I could only get the light brown/tan case which is utterly hideous and doesn't fit the cable at all. These also came in a bag instead of the nice metal case of the M1's, and aren't exceptional either really. I wouldn't bother wight the M1's or these.
The Tingo's on the other hand, are the exact opposite. The mids are slightly recessed, whilst the Bass and Treble are brought forward in the mix. As somebody mentioned earlier, the Treble is so powerful on these I sometime found it overwhelming, but overall the sound on these was preferable to the Dasetn's. The soundstage also feels bigger (however it still pales in comparison to the Senn's and is inline with the PK3's. Ive been using the foams on all the new buds as the shape of the body is harsh and geometric and not nice on the ear. The packaging for these isn't worth much mention, but at least they come with a case.
(tldr) I'd recommend anyone thinking about buying new earbuds only bother with the Tingo's for the Chinese brands, the MX471's for the Senn's and the PK2's for the Yuin's. (I haven't tried the PK1's, however I'm not sure the leap would be as large as you would hope, similar to the gap between the Senn 471's and the 985's)
-My major reference song for the testing of these buds was a lossless CD rip of "Little Secrets" by Passion Pit (as well as an assortment of other contemporary music). I have 1300 plays on this song alone in my iTunes library, and know it like the back of my hand. It has good examples of highs, extreme lows and swelling mids in the verses, as well as clear, modern studio vocals which give a good idea of clarity. I use this song also because played in the wrong headphones, the Sine waves can sound clinical and cold, and make the nature of the speaker immediately obvious.
-I have been driving all the headsets WITHOUT an amp, using my Macbook Pro primarily and occasionally an iPhone 5c.
Sorry for the long post all. I hope this helps some people out there like me who where struggling with making a few of these purchasing decisions.