I did get 10% off, but that was supposedly because I was originally going to buy the SR225s but they were out of stock. Perhaps the clerk was being dishonest, and they were already 10% off.
The only differences are a different color, thicker cord and a different driver material, correct? The 325i already has a high-quality UHPLC cord, so I doubt a slightly thicker one will make a difference. It's a shame if the bass is improved in the new model, but the 325i already has renowned sound in that department, so again, I have to question whether there's an actual difference. I do prefer the gold over the silver anyway...
It would be great if anyone who has compared these models can give some input, but I doubt there are many who have switched from the 325i to 325is this early.