"We've been purchasing the Zebra Transmatte 2000/4000 compatible labels over the past two years, the labels work flawlessly with the OEM Zebra ribbons at a fraction of the price of OEM Zebra's. I haven't tried their 3rd-party ribbons though, they are a bit pricey compared to Zebra OEM ribbons.
So far service has been great, they ship fast."