It isn't an installer, it's a stand alone app. Atm I've still got FSD as default and I can run Aurora as needed too but despite being alpha it's pretty solid. I could definitely see using it by default. It seems like they're going for a more simplistic streamlined design and even the alpha seems to handle that pretty good. It managed to scan all my folders and get pics in probably a quarter of the time it would of took FSD.
edit: Honestly probably the only reason it isn't my default yet is laziness. It definitely will be soon. Like others have said FSD always felt like unleashx (xbox 1) to me and this feels like homebrew on the 360 should.
2nd edit: I downloaded a new game so I thought it'd be interesting to time FSD and Aurora at scanning my hard drive (aside from the new game both already had their library's built), my hard drive's got 900gb worth of content already but FSD took 7:25 and Aurora took 3:10. Obviously these numbers are very scientifical and should be taken quite seriously