In my experience -- I've owned two -- the android tablets all have the same flaw. Beyond the super-cheap build quality, android can't conserve battery while sleeping. I can leave my now-4 y/o ipad in my backpack for a week and it will lose perhaps 10%. My androids would be dead. Hence I never use them.

Oh, and because no-one uses android tablets, no one makes good apps for them. eg the nice pdf readers -- I use GoodReader -- are all ios.