They are pre-flashed with an android version, which isn't really stable, and actually is quite unusable, apart from browsing the web.
On the marsboard site they offer some ubuntu flavours. I will probably give these a quick try. And afterwards either invest some time to get it working with either Debian or TinyCore.
I also bought these boards because of all the I/O options, and especially the line in. I hope I will have some time to play with the boards this week. As soon as I have some interesting results I'll give some feedback.