I currently have the Polar Express LC set with the puffer smoke unit (7-11022). I've had to rebuild the smoke unit once already and I am beginning to really dislike it. Modifying it would be a nightmare. I've tried once already, but I've learned a lot since modifying my CSS and doing my current project with the MTH SP Daylight GS4. I want to stay with the LC line but want a fan driven smoke unit. Can any of you folks be able to help out with this and make a suggestion?