I am happy to say I am writing from a CM Quickfire XT, equipped with a Vortex Thick PBT 104 keyset (Orange on White Doubleshot).
![Cheesy :D](https://cdn.geekhack.org/Smileys/solosmileys/cheesy.gif)
It arrived yesterday and I was eager to install them. Finally I have this sweet, sweet PBT feel
![Azn ^-^](https://cdn.geekhack.org/Smileys/solosmileys/azn.gif)
Here is my story :
The board with original keycaps removed :
![](http://i.imgur.com/a79YP18.jpg)
Surprisingly, I managed to remove all the caps with my bear fingers and without the help of a keycap remover - my other CM Quickfire XT is a Cherry MX Blue one, and its caps can not be removed with bear fingers!
The board was a bit dirty :
![](http://i.imgur.com/t0Jifsq.jpg)
I cleared it a bit :
![](http://i.imgur.com/Js7V0az.jpg)
New caps :
![](http://i.imgur.com/kJKC4cm.jpg)
Job done :
![](http://i.imgur.com/9hMYvdK.jpg)
I had O-rings ready for install, but when I tried both with and without them, I chose not to install them. The sound is way better without O-rings!
So my verdict is Vortex caps are good (at least this model).