Nikon 1 J1 / J2 / J3?

Which one has the best specs?

It all comes down to your personal decision.
And which presents the most value to you.
There will be no difference in photo quality between the J1 / J2 & J3. The J3 just gives you a few more features.

Here are the specs, side by side.
http://www.dpreview.com/...s=nikon_j3

As you can see. There's very little difference. The J3 has a faster frame rate for continuous shooting. The J2 and J3 have a higher resolution screen.

1. J2 and J3 have greater resolution (14.2) compared to J1 (10.1 megapixels)
2. J3 has Wi-Fi via an adapter, J2 does not.
3. All of them have the same frame rate: upto 60 fps depending on the setting.
4. The biggest difference is: J3 focuses at 15fps (the others do not). At higher fps, focus is fixed at the first frame only.
More on this series below.