Depends on what you are looking for.

If you only care about looks, then drop it as much as you want, but you will have problems with camber being all over the place at the rear, uneven tyre wear, front driveshafts popping as said above, etc...

So, in summary, it will look great but handle like a bag of shite unless you re-adjust the camber.

I have been advised that the best compromise handling wise is to drop the front by 25mm, and leave the rear standard, but it doesn't have the "slammed" look