Here is another review of Android tablets:
http://www.techradar.com/news/mobile-computing/tablets/15-best-android-tablets-in-the-world-905504
I liked the look of the Nexus 10, but it doesn't have an SD Card slot, nor a SIM card slot. Screen resolution very good though.
In my case, I have gone down the Apple route and bought an iPad4 64GB with 4G, etc. Android, Blackberry, Win, etc. was not supported by the device I wanted to use it with, so no choice in my case. The application also needed a bit of grunt.
What do you want to do with the tablet?
Grey Beard