I rather split them up.. Hamhuis and Tanev compliment their other partners well defensively while their partners can either go out offensively or have a slip up and have Tanev/Hamhuis cover them
I wouldn't mind seeing a bit more of this pairing just to see how they work together. Tanev's pretty cool though he seems to gel with whoever they put him with. Hamhuis is Hamhuis and isn't the D I worry a lot about.... yes casual Kev I am talking bout you.