"Pro Xify" won't get around trademark infringement. Trademarks not only cover a sequence of letters, but even similar marks (Mike Rowe, his real name) found this out when he registered MikeRoweSoft.com. The Nissan case doesn't have anything to do with this situation. The Nissan case deals with a prior usage claim - and all these domains were registered after their trademark filing. This is a situation where the domain owners were well aware of the company(s) names and registered them for that reason - to ride their goodwill. They may not have known it was trademark infringement, but this isn't a case of where someone came up with these names out of the blue (which wouldn't be a legal argument anyway).