The 16x16 Supreme 530s are on backorder, but I found that the 16x24 size isn't. I actually prefer a larger microfiber myself as it gives you twelve total sides instead of eight. As for the Supreme 600s, I recommend the Chinchilla as a replacement. The 16x24 is currently on BOGO, as are the Miracle Towels (great alternative to the Gold Plush towels).