I have replaced clutch slave cylinders before, but not on a MB,, if the clutch cylinder is leaking,, you should feel it in the pedal ( soft and or spongy } or when you try to shift gears,, the clutch may not fully disengage,,
I can not comment on the brake slave cylinder for MB just had my MB for 6 months and all I replaced was master cylinder, rotors , and rear park brake shoes ,, I would get the advice form some one who has done that specific job on the same model / year car as yours..and be very careful ,,,ps in the photo I have 2 jack stands also,,

Attached Thumbnails