I got an S560 for myself and one for a gift recently. I don't have another BD player to compare it to and only played 5-10 DVDs so far, but it seems quite nice.
Wifi connnection is very useful and easy to set up. Configuration options plenty. I don't mind the whole front opening up, although it's a little weird. I also like the ability to change the display to bright, dark, or off.
Speed is ok, I guess. I don't have another player to compare it to, but it's not instantaneous. Mostly, it doesn't bother me except when I push the eject button, sometimes it takes way longer than it should need to open up. I can't imagine what it's doing in those 20ish seconds.
The other quirk is that there are a few menu options, like main menu or pop-up menu or home menu. Depending on what the DVD is doing (main movie, logos, warnings, screensaver) one or more of these menus will be disabled. While this is not unexpected in some cases, other cases I find myself trying all three menu buttons just to get something to react. This could be a disc issue and not a player issue.
One thing I'm surprised not to see here at AVS are recommended player settings. Are there no customization options for this player that are worth playing with?