I recently contacted Umnitza.com for a replacement ring for a set of DDE rings that I was installing on my maxima and they were great! Communication was awsome, with emails returned the same day. Shipping was a bit of a hassle, not in terms of delivery time, but is receiving a ring that was broken. I contacted them about the problem, and they quickly shipped out a replacement ring ASAP. I would definately deal with Umnitza.com again.
Mike