I've had the 65t for almost 2 weeks now. At first I wasn't impressed mainly due to the sound signature and was actually considering sending them back. The app's EQ didn't help anything either... thought it was pretty rubbish. Tried adjusting via the built-in EQ for my S9+ which improved it slightly but never to the point I was going to be impressed. They sounded veiled, plasticky and with forced bass response (probably from over-EQ-ing to attempt to make up for the total lack of any kind of bass impact)...BUT.... then I changed tips to some bog-standard ones I had laying around and everything changed!
I have seen the tip mods in this thread but I didn't even need them. When I first tried it out, the fit was obviously too loose and taking the TW's out would leave the tip in my ear every time
I found however that if you push the tips further up on the body, without any need for a mod, you could actually slide them beyond the initial point and have them grip further up the stem so now the tips never come off by themselves. This also allowed me to better position the actual body in my ears as well. Better fit AND hugely better sound!
The seal is so good now that passive noise canceling has increased substantially which in turn makes you appreciate the hear-through feature a lot more.
On the microphone front, everything is great when you use them in a quiet environment and my wife has commented that the SQ is great. When you're out and about in a noisy environment however, that changes tremendously and they pick up anything and everything around you. Leaving both earpieces in at that point makes you very hard to understand to the other party.
What I've come up with however, is to do exactly as you would with wired earphones where you keep the mic in your hand close to your mouth as you walk around. In this case you just take one earpiece out and use it as the mic close to your mouth. It works really well and even though there is still a lot of extraneous noise that gets picked up, at least your voice will come across quite clear. Just make sure you keep the sensor covered for the earpiece that you have taken out so that it stays connected and switched on.
All in all I now absolutely love my Jabra's and there is no way I would send them back. Great battery, hear-through, small case, good fit, good SQ, doesn't stick out of your ears in the same way other ones do, price I paid was at 40% discount... couldn't be happier and I can't envisage myself going back to full wired or BT wired.
Only remaining niggle is the left bias in terms of volume which I also suffer from. Here's hoping Jabra will implement a balance feature in their app!!!