I have read several strings about cross drilling rotors. I have done this in the past with near disastrous results . Here is a post from another Benz site. Read and learn so you don't have to learn from experience.

Date: Thu, 22 Feb 2001 17:24:18 -0500 (EST)
From: "Richard J. Sexton (Mechanic Role Account)"
Subject: Re: [BANNED] One more little thing

Have you tried the ATE power discs Roger?

At 04:53 PM 2/22/01 EST, you wrote:
>Alvaro suggests:
>
><< Cross drilled rotors do 2 things.
>
>1 reduce un-sprung weight.
>2 allow gasses to escape from the brake pad under extreme conditions.

>There is one more thing that cross drilled rotors do (brake discs, more
>accurately) and that is CRACK. They all do and cracks lead to breakage.
>Further, no manufacturer uses drilled discs. Those holes are cast in the
>disc. Drilling leads to stress risers which leads to an appearance much like
>a pizza with a piece or two missing.
>
>Don't even think of drilling your discs. And no, countersinking the hole will
>not help.
>
>Roger Ellingson/Seattle
>