I'm no legal expert so I'm using a license text used by a big brokerage of 3D models.
The thing is that it is OK to use the models in renders and animations and publish these as you wish. The only thing that is not allowed is to redistribute the mesh (=the source). This is stated in legal mumbo jumbo in the license file but I guess I will have to completent the legal text to make it clearer.
Example:
(1) The Viggen was purchased by an agency using it in a TV-commercial . This is totally OK!
(2) John Doe buys a copy of the Viggen, makes renders and sell the prints.
This is totally OK!
(3) The Viggen is purchased by somebody who converts it and distributes it to thousands of people.
This is not OK
I don't wish for a legal discussion but I will complement the license file with examples in the future.
And here's an extract from the license file if anybody is interested:
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LICENSE FOR ITEMS PURCHASED THROUGH WWW.COLACOLA.SE
This license only applies to items purchased through www.colacola.se. It is the Buyers responsibility to read and understand this license.
The Artist (Author) retains all copyrights to the enclosed materials. The Buyer is not purchasing the contents, only the right to use the contents. The Buyer may not redistribute this archive file, in whole or in part. The Buyer may not store it any place on a network or on the Internet where it may be referenced by a third party. Buyer acquires the copyright to any derivative works created using this work, provided none of the original materials can be extracted from the derivative work by any means. If Artist can show that any of the original material can be extracted from Buyer's derivative work, Artist can demand both the original and derivative work, and all copies thereof be deleted. For example, Buyer cannot make an image of a texture map mapped to a flat plane, such that the original texture map can be cut & pasted from the image. This is designed to protect the Artist from Buyers releasing work, which lets other users obtain the copyrighted material, and is not meant to infringe upon the artistic endeavors of the Buyer. Buyer may not make any MetaStream animation files with the enclosed materials, until this format can protect the original materials from being extracted. Items sold at www.colacola.se may not be used for illegal purposes.