I must be part of the 1%. I received my Sensaphonic custom sleeves for my 535's on Friday. My "Sensaphonics Gold Circle Audiologist" had a hard time helping me insert the sleeves, even with Oto-Ease. When I finally got them in, I did a seal test using their website on my iPhone: http://www.sensaphonics.com/audio/simul_tones.mp3
As stated by others, they look ridiculous and stick out of my ears about 1/4"-1/2".
I had a good seal in both ears at first, and was pleasantly surprised. Then I opened my mouth and instantly lost the seal in my left ear. I re-positioned the IEM and tried again. Once I finally got the seal and double checked with the test tone, I clenched my jaw a bit (something I regularly do while drumming) and the seal was gone again; no bass at all. So, I figured I had a bad impression in my left ear. Fair enough, I would have to get another impression made within 30 days, and wait another 3-4 weeks to finally get a good set of sleeves.
In the meantime, I got a good seal and made sure not to move at all. I opened up Spotify and streamed some tunes I had been listening to a lot last week, so I was very familiar with how they sounded. I only listen to 320 kbps or lossless audio. I also have a full Schiit stack (Wyrd > Modi 2 Uber > Magni 2 Uber). I know what good quality is and isn't. The sleeves (with a proper seal) sound AWFUL. Essentially, they sound like you're listening to a speaker that is 50' away down a 10' diameter tunnel. It sounded like someone changed my 320 kbps quality setting down to 56 kbps. Either the shape of my ear canal does not work with IEMs (is that a thing?), or these are severely defective. (Note: If you look closely, you can see the impressions of the Shure model number on the sleeves themselves [one of mine is "535", the other looks like "215"]. I made sure to line these up exactly to ensure the IEMs were properly placed in the sleeves.)
So, this morning I called Sensaphonics. Got their machine twice, and left a message to call back. Hopefully they return my call to explain why these sound and fit so poorly and will work with me on getting proper sleeves. If, after another long 3-4 weeks, the next set comes back the same way, I'll expect a store credit for something else (apparently refunds are not offered "under any conditions"
).
EDIT: Got the call back from Sensaphonics. They assured me that they would take care of both issues. The audiologist will take two new molds; one with me being still, and another while I "air drum". I'm going to try and get the molds done tomorrow, so I should be able to report back in 3 weeks or so with the results!