I have had been testing Silencerco's Osprey suppressor on both a 9mm and .45 XD for close to a year. Both XDs were set up for a suppressor by Springfield's Custom Shop for articles for Combat Handguns. Dave and company installed extended and threaded barrels and also did sight and trigger work on both guns.
The Osprey is an ecentric suppressor that allows for the use of most stock sights. It is a very effective suppressor and the design allows for a significant increase in internal volume when compared to traditional round suppressors of the same length.
The .45Osprey averages about 129 db when shot with white box 230 gr. FMJ ammo. When shot is 5cc of water, it registers in the 119 db range which is about what a good .22 LR suppressor registers with CCI sub-sonic ammo. I can attest to these figures as I was the one shooting the pistols!
Can't say enough good things about both the Custom Shop and the folks at Silencerco.
Here are a few photos.
Here is the 9mm with the Osprey and a SureFire X300 attached. The sights are Heinie Straight Eights with tritium inserts. They were also done by the Custom Shop.
Here is the .45 XD with the 45Osprey.
The Osprey has a locking cam that allows the suppressor tube to be properly indexed on any weapon. It is shown here on a Nighthawk Custom GRP Recom 1911. After mounting the Osprey, the locking lever is opened, as shown, and the suppressor body is properly aligned for the specific pistol. The lever then locks the cam. The suppressor stays indexed for that particular pistol and will only need to be re-indexed if you change host weapons.