First I used GTTabs, which is very nice because it's SO simple as to the code. But then I noticed that the features are too simple, people did not recognize it were tabs (no shadow or whatsoever). The layout of my site became disturbed. See: http://booxalive.nl/phaethon/
So now I've found this one and I love this plugin, though the last updates are not really recent. :-/
So many variety's are possible, there is always a BEAUTIFUL version that suits your site. I am very happy with it.
The ONLY disadvantage is that this plugin cannot handle WOWslider in its tabs. But that is a minor issue for me. In the GTTabs the WOWslider performs perfect.
And you can use those plugins together: WP-UI tabs next to the GTTabs, no conflict at all!
I CAN RECCOMMAND IT TO ALL, ALSO TO DUMMIES! :-)