I ordered some seeds for the variety Katja last winter,
http://www.adaptiveseeds.com/node/107 .
The service was fine, and I was very satisfied with the quality of the seeds. The Katja tomatoes/plants fit the catalog description and produced some very good 3 to 5 ounce tomatoes for me growing in five gallon containers.
Next year I will try growing them in containers as well as in my garden beds.
Stuart