The problem here are the 2 small 6" pipes. When that stove is crankin I don't think the 2 runs will wash enough heat off of the stove, making it less efficient and sending much heat up the smoke pipe. I know that your in a bind for space, but. My daughter is heating her 2000' home with a Hyfire II and has not started up the second burner yet. She has a jacket with 2- 8"runs with duct fans half way up the pipes. One is about 6' from the the stove, the other is about 8' from the stove. So far no trouble but she is only burning 1 burner. Because of your 6" pipes I'm afraid to say what the temps of the air would be. There are many factors that play into this. Basement air temp, speed of the duct fans, if the air is directional or does it need to go around bends causing back pressure etc etc. I would be lying if I told you the fan motors won't burn up, because I don't know, and neither does anyone else. When you place the duct fans near the registers they can drive you crazy with the noise. This is a tuff call, and I think only you can make it by trial and error.