A friend of mine had a 'extremeracing' deck which he liked alot. I personally havent tried a carbon deck. I dont know what weight diff there would be. Are you racing?
On another note i found my main diff problems (as previously discussed) were because the diff cups, where the 2 bearings sit on the pininon, were warping under pressure even after shimming causing the pinion to move away from the main gear and thus stripping the pinion. Ive read this is a common problem.
I have read of stronger diff cups available, alloy. Any exact brands anyone has tried?