Since someone asked me about some IEM recs via PM specifically how the JVC FXD80 compare to the current crop of budget-fi wonders....
Pretty relevant since someone just asked here:
The FXD80s are pretty good sounding so you can't really go wrong with them. BUT and that's a BIG BUTT going with a "mainstream manufacturer" doesn't always equate to better sound or better customer service. And in your case these JVCs are only sold in Jpn so if you have problems with them good luck sending them back for returns/refunds/exchanges. Same could be said for those Chinese IEMs but therr are trusted sellers like Penon/bigbargainonline that has 1 year warranties/ very good return/ exchange policies so..... there is better safer avenues/ options to get those Chinese IEMs when there are problems with then compared to their Jpnese counterpart.
Since we are on the topic of quality control, you should skip the Tenores by default based on all the bad experiences head-fiers have had with them.
So that leaves you with the Ostry and TTPODs and the FXD80s. If passive isolation is not your top priority the Ostry is the best sounding most technically capable outta' the three, cuz they literally will make those FXD80s sound like childs play in tuning with their great bass texture/quality, VERY wide soundstaging/ lush 3Desque mids and amazingly extended yet never overly bright/harsh nor sibilant treble. These Ostriches are real dealios yo' no hype and they just have this unique old school organic analog sound character to them that is akin to the VSonic GR07 BEs which many head-fier praises to no end.
The TTPOD T1-Es on the other hand has less texture to their sound and is tuned more like your conventional bass centric IEM meaning the 1st thing you will notice is their big bass and very extended treble, almost that classic "V-shape" sound if you will, BUT this is not the case here cuz the mids on these TTPODs are just as forward and lush as their bass quantity/quality along with their extended treble. So what you have/ get with these TTPODs is a true audiophile basshead IEM that does justice to every aspect of the sonic spectrum and leaves nothing behind cuz you literally gets it all, esp in the bass.
I have burned in my T1-E for the past week non-stop and their bass has improve quite a bit along with their treble. It's bass post burn-in has settled down some, and has increased in texture giving it a more spacious/ roomy atmospheric sense to them unlike previously where you just get hit by a big dose of it in a concentrated narrower range. So in a sense the bass has became more enveloping with better texture and flavor. The treble has also became less bright and less fatiguing but yet still remain very well extended, though still lacking that refined sparkle and shimmer. All in all these TTPODs are now even more well balanced and is a SERIOUS power house of an IEM that holds no bars!!! For $36-$50 these are a steal!!! And is much better deal/ more capable IEM than those FXD80s. The 80s in comparison sounds tiny, artificial, cold, sterile and a bit lacking tbh.
For me though the Ostry is the best outta' all of them due to their unique and non-fatiguing spacious and very atmospheric textured sound that is EXTREMELY easy to drive. The TTPODs takes 2nd spot if you want very good passive isolation and a more conventional type of sound signature/ tuning that is medium hard to drive, an amp will no doubt make them better. The JVCs is last and is a bit dated for the performance to price ratio esp. with so many heavy hitters these days. They were great like 2 years ago but can't really hang with the current crop of budget-fi sonic wonders.
Hope this helps.