I'm in the market for a Windows RT device

I'm looking to buy a relatively inexpensive computer (tablet) for my family. Something that all four of us can share, and can also function as my dad's primary computer. He doesn't do much.

I'm set on Windows RT, I'm not going to get an iPad or an Android tablet. I was going to jump on the Surface RT the moment it is released in my country, but this video changed my mind:


I've seen the RT devices from Dell (XPS 10), ASUS (VivoTab RT), Lenovo (Yoga 11), Samsung (ATIV Tab) and of course Microsoft (Surface RT). And only the form factor of the Surface and the Yoga seems alright to me, but I still really want the Surface. I'm a fan of Dell, but I don't know how a dock would work in my family.

The Surface RT, as much as I want to love it, has been a disappointment. That's not to say that I'm not considering it anymore though.

Nokia seems to be coming up with an RT tablet too, and I'm also a fan of Nokia, but is it going to perform as bad as the Surface?

So what should I buy?