I can tell you that the brake fluid on my 86 560sl, which had supposedly been serviced 6 years earlier, looked like rusty milk. Worse, I had to replace all four (4) calipers. One was totally frozen, 1 was very stiff and I'm sure was going to fail in the next several months, and the back two were found to be seriously pitted after I had disassembled them (with great difficulty) for inspection.

The prices for NEW calipers are eye-popping. I don't think you could get 4 for under $800 and never mind the PITA/expense of installing them. I got rebuilts from advance auto (so far, so good). So, especially if you do the fluids yourself, preventative maintenance can be a money saver.

Now, as far as the safety is concerned; what you have read about boiling points and the hygroscopic nature of this stuff is true (I read up on this because I couldn't beleive it either). Your brakes will NOT be as good in an emergency if you don't change the fluid every few years, never mind the corrosion issue. This isn't a property unique to MB cars and brakes.

Very new cars may be using a newer fluid, which is much better and not as hygroscopic Unfortunately, as far as I have read, you can't just replace the older-style fluid with this stuff unless you have the whole thing professionally flushed, which is probably beyond my MITIVAC. There may also be compatibility issues with the rubber hoses.