Such a pity mate! The same thing happened to my brother and he had to send his back also but he really wanted that SLP look so he ordered a plain black pair of SLP, got them hemmed and did the knee rips himself. He took detailed photos of how they looked and he said there was loads of great videos on YouTube showing him how to do it. It worked s treat, you'd never know the difference.
I have to agree with you about the difference in quality...