I've attached mine to my Sennheiser HD25's. Originally I considered purchasing a HMD-25 cable and putting it on my HD 25-1 ii's, however after further research, this would be difficult to find, as well as pricey if I did find one. Thus the ultimate solution came to be the AntLion ModMic. This attache mic is well regarded in the gaming community for it's clarity and natural voice reproduction, and "good" noise cancellation. I can vouch for it's sound signature, but can't say much for noise cancellation!
The mounting system is VERY secure, and you won't have a problem with it just randomly falling off, although be careful with how you tug on it as it can pull away easily when being brought down or going up. I really wish the magnets were black like the clasps, but can't be perfect I guess. The cable is slightly too thick to utilize the HD25's cable management, thus forcing the mounting to the right earcup.
Overall a solid product, maybe a little on the expensive side at first glance, but for what you get when you receive it, this is a SOLID purchase if your looking for a simple add-on mic for your expensive headphones.