I had previously the Archos Arnova 8 G2 ordered, in which I, however, access to Google Market was missing. That's where the Odys Xpress. I summarize briefly my pros and cons for the tablet together:
+ Budget (my purchase price was 156 euros)
+ Display is capacitive and very responds well
+ Display aspect ratio is 4: 3 (I find surfing much more pleasant than widescreen)
+ Google Market
+ Mini HDMI output
NORMAL + USB input (keyboard, card reader, no problem)
+ Stable (you have to press quite substantially behind that you see discoloration on the display)
- Display is very angle dependent (but hey: 156 Euro!)
- Wi-Fi is a bissl weak (for my 53sqm apartment's arrived but loosely)
- 512 MB RAM in fatty websites bissl thin (Task Killer should anyway be compulsory)
I would buy the Odys Xpress immediately, now maybe even the Cosmo. However, I find the 8 inch size in 4: 3 format an ideal compromise between size of the display and mobility.