Even though you may not be able to utilize the SHSH blobs you save for A5(X)/A6(X) devices at this time, you may be able to in the future (Future loopholes/exploits)!
The beauty of this feature is there is no need to provide an IPSW or push new iFaith updates just to save the latest SHSH blobs from Apple [just like the TinyUmbrella days]. (Send some love to @icj_ and @iNeal for their lovely APIs powering this new ability in iFaith).
Mac Version?!:I'm working with @Djayb6 on getting iFaith fully ported to Mac OS. I can't provide an ETA as to when it will be available, but keep an eye out for it! :)
A5(X)/A6(X) Support?!:Devices equipped with the A5(X)/A6(X) processor do not currently have any known low level iBoot or DFU exploits to jump start the iFaith payload to initialize the dump and restore. Therefore, support to dump blobs for devices running these processors are not possible at this moment in time. (You can still fetch the latest blobs directly from apple though by clicking the "Show Available SHSH blobs on Server" button.)
A5(X)/A6(X) Downgrade?!:As far as downgrading on A5(X)/A6(X) devices goes... There currently is no publicly known loophole to kick-start a downgrade. So at the moment there is NO public way of downgrading an A5(X)/A6(X) device. For A5(X) devices that have 4.x.x SHSH blobs cached or still running 5.x.x, redsn0w can recycle the first apticket loophole and *re-restore* your device as long as you have the essential SHSH blobs. More info on that here.
Report any issues to iH8sn0w via Email (iH8sn0w@iH8sn0w.com) or Twitter (@iH8sn0w)
Download iFaith-v1.5.8 (for Windows)