I got the premium package, but only for the front axle. Cost me around 240 shipped. The stopping power is about the same as oem, I don't feel much of a difference. but then again, I haven't been doing much hard braking.
There are a few things I need to warn you about if your gunna buy these.

First, you might have a little trouble finding a place willing to install them. Places like justbrakes and pepboys wont install them because those were not OEM mercedes parts, saying it was a liability issue. Couple places that would install them tried to rip me off, so be careful. I finally got them installed for 90 bucks.

Second, the brakes make a very slight buzzing noise when braking, which may be due to the rotors being slotted. It is only audible when the windows are down, and recently a very slight squealing noise has arisen which only occurs at very low speed braking (ie at a Drive-thru) and only audible with the windows down. it does not occur when coming to a stop at an intersection for some reason.

Third, there is a slight burnt smell coming from the brakes after a drive, which cant be good, lol. I think its because the rotors and pads were just installed, and it was just the brake-parts-cleaner thats being burnt off, but i dont know...

yep..