Holy Crap! That spring compressor are only meant to compress the Mcpherson strut type spring... you know... the spring located inside of the struts... not MB springs except the new C class which uses McPherson struts.
Even as that picture show, that guy did not use the safety hook that is supposed to be used with those compressor. The reason he didn't use it is because they don't fit... too small.
McPherson strut type springs are only 1/2 the thickness of MB or chassis springs. and are far weaker in spring tension strength...
I used Sir Tool compressor and it has failed on me too. I was lucky I only hurt my wrist.
For Oneguy... I suggest strongly you get the MB service manual and study what is involved before you do it.