Anyone tried these with the IE80? I've got a pair coming from Jaben (didn't see that Dopaminer was selling these) for some Flare R2As and would be interested to see how they work on my Senns. It took quite a while before I found tips that worked for me on these IEMs (Auvios).
To be honest, I think that the spinfit work for some people and not others. I've found that the tips don't always fit, but other times they fit well. The tip pivots which sounds good in theory, but to me, I think that the pivoting sleeve make them less predictable during insertion and so sometimes I either get a good fit, or not at all.
Comfort-wise, I would rate them below JVC SD. But that's just me. Sound-wise, definitely below JVC SD. They sound good when they fit. But not incredibly so. The JVC SD on the other hand seem to actually change the sound assuming proper fit compared to others with similar fit. I've had others concur that the Fidue A83 work best with SD and not spinfit. When I used the spinfit I got good seal, but the sound was untamed and sibilant. JVC SD, and the sound is smoother, better rounded and definitely tames the higher frequencies.
I have tried with IE8, but the sound doesn't seem all that different, although bass feels stronger. Still prefer JVC SD in most cases.