IMHO you are more likely to find the excessive unloading of power to the front wheels annoying enough to remove the traxxas CD before you will break one. There are of course exceptions to that obviously, but it seems that most people find that high powered brushless systems and the traxxas CD just don't work well together. Having only 2 spider gears the CD does not have much internal resistance (compared to say 1/8 scale CD's ) which requires you to run very heavy oil/lube to compensate.
I run the center diff and like mentioned the front wheels get all the power... I did put in some pretty stick diff grease, but I will be putting in the thickest stuff I can find.. when I can find it.
I went with a center diff because I was wasting gears in the stock tranny. Is there a way to make the tranny stronger without going to a center diff?
As far as the center diff strength. it think its pretty strong, but I'm only putting 4s to a 1512 Neu.
I tried the thickest stuff I could find (ofna diff lock lube) and still had more unloading to the front wheels then I wanted.
I replaced the tranny 2nd gear set (tranny is locked in 2nd and uses motor braking) with a steel set from RRP. It does add a little rotational weight but since I don't race it's not an issue for me.
I think that part of the reason the stock gears get torn up is heat. If your gears have a distinct groove cut through the center of the teeth then this is likely the case.