I had a cheap mic (AT2020 I think?), and I bought this because the 'official' shockmount was almost the same price as the mic.
It fit, and it worked reasonably well - but it was insanely tight, and incredibly difficult to open. When I first bought it, it was almost a two-man job to get a mic in it (though it did ease up a bit).
There was a small piece of felt inside, but at the opening of the ring, there's two metal tubes (which hold the spring levers you pull to open it up) which scratched the hell out of the mic. Not ideal.
On a slightly smaller mic, maybe it wouldn't have been an issue, but I measured the mic and bought the one that should have fit it.