I looked into this several years ago. I grew the red centiflor the last two years. The number of flowers is amazing with the fruit set not as high. I am trying to find pictures, but no luck so far. I got my seeds from caseys heirloom tomatoes of airdrie but I just checked the site and they were not selling them this year. I found this link
http://alanbishop.★★★★★★★★★.com/thread/2244 which might be helpful. I made several crosses and am planting some f2's this year so we will see what happens.