He has a tendency to be rash, like Skrtel. Though Sakho's weapon of choice is the occasional slide tackle in the box.
On one hand, it's exciting to watch when he times them right. On the other hand, it's playing with fire and you just know that the first time he'll misjudge one it will cost us points.
There's an old saying... "good defenders keep clean sheets but great defenders keep clean shorts". For me, this is an area in his game he needs to improve.
I think that in the current formation, the role of the middle CB will suit him best and will allow Agger to be on his left with Toure/Skrtel on his right.
What will happen when we decide to revert back to 4-3-3 for tactical reasons? Don't know but I hope that in training both Sakho and Agger are working to find out who's more suited to play RCB.