First the all-around specs:
Each of these items let you reach the internet through BD-Live with your Internet connection. You can connect to your favorite Internet entertainment venues such as Youtube, Netflix, Slacker, or Facebook. Though unlike the others the N460 model uses BRAVIA Internet Video platform to reach the respective providers.

Just about every Sony device has a quick startup and these 3 make no exception. Fast boot-time of 6 seconds but the S570 gets ahead of the others in terms of audio/video streaming over the Internet.

Now for some of the differences:
Compared to the S570, the picture quality on the older S360 is superb, whereas the S570 has decent quality for Blu-ray and DVD. The best of the 3 is the N460 because it supports Dolby TrueHD and dts HD codecs, and even if the S360 also supports the same advanced codecs it almost rivals the former mentioned N460.

Another issue is DVD upscaling. All 3 are supposed to do this but you get the best quality from the S360 and the S570, while the N460 has quite sluggish quality and may sometimes look out of focus.

One feature exclusive to the S570 is the Gracenote that shows some extra information on the title but resets the movie to the start position, so it’s not necessarily the game-breaker.

Conclusion:
While the S570 may be better than the N460 in some respects, consider the fact that the N460 is about a quarter cheaper. The S360, being the cheapest, can’t really compare but does a surprisingly good job nonetheless.