I picked one of these up for a bit less than list price and am very happy with it.
Yes I spent > $50USD on something that JMRI can already do with my existing home wireless, but I'm the sort of person who writes my own signalling logic on an Arduino so that I can flick a switch and my layout is ready to run - it takes longer for my phone to switch routers than it takes for the layout to be ready to be used.
Worked out of the box, although I did enable WPA2 and changed the password just out of habit.
Like all of the Wi-Fi throttle solutions, I think the Android based throttles are probably a little better as you can use the volume buttons for more tactile speed increments, but it works just fine on my iPhone with the screen slider.
I find the phone much more convenient than the standard smaller (at least Digitrax) wireless throttles as I can flick through the screens to access all of the functions and send switch commands from the phone.