Does not meet the original earpads

First of all, let me say that I myself do not accept reviews with one star seriously, but with this product I have no choice.
After a few years in use, the ear pads on my Porta Pro have dissolved so slowly. No problem, in my view, are of this type ear pads wear goods. I then made me at Amazon on the search and came across this product and ordered it finally, because I wanted to have the original earpads.
Nope. It stands on it Koss, but comparable to the pre ear pads at Porta Pro are in any way:

- The color is black with a neat stitch Blue
- The foam is much harder than in the pre-assembled
- The feel is cheap, these things feel even slightly like Styrofoam
- You are a little thicker and harder. It makes them feel not so soft to the ear

- The biggest point of criticism: the sound characteristics of the Porta Pro is completely changed. The headset sounds with these ear pads to saftlos and tinny. The Porta Pro is unbeaten in price-performance ratio - but only with the supplied earpads. These ear pads it sounds cheap.

Personally, I am very surprised, what the ear cushions on the Porta Pro for an impact. Thus, for me, a big question: Why Koss does not sell the ear pads are pre-assembled in a new Porta Pro?
Now, the search for the third-party los.Genau I wanted to avoid.