Gas Inserts

The following web page: http://hearth.com/what/gasinserts.html had an article with the following information:

Recently, a new breed of Gas Inserts have been developed that do not need a chimney liner. These units are built to be less efficient than the regular inserts, therefore throwing a bit more heat up the chimney. The chimney can therefore draft well without needing a liner. This new breed of inserts sell for $900 to $1300 and include blowers and glass doors as standard equipment. Installation involves slipping the unit into the fireplace and connecting a gas line--- around $200. to $300. in most areas.

I'm intrigued by this "new breed", but I don't know how to go about searching for this type of insert? Is there a generic name that is used to reference this "new breed"? Can anyone recommend a make/model in this category or provide any additional detail that will allow me to search for these?

Thanks

Before this gets buried pages back, any ideas from anyone?