baffle or cat?

i have a fisher insert that i installed on a well built hearth. my chimney consist of 6' single wall and 12' of double wall class a chimney. the problem i have is when i get a fire going good the flames go straight up the chimney, very uncomfortable to me. i am flirting with the idea of fabricating a baffle (much like the ones fabed on other topics) using angle iron and firebricks or making a slide with a cat. i have a neighbor that has a carolina cat stove that resembles mine. i am leaning towards the cat modification, only debate i have is cost, a well built baffle will need minimal maintenece and a cat will need replaced. what i am looking for is folks that have tried this, specifically the cat modification. after seeing my neighbors stove operate i was really impressed. again, the main reason for these ideas is to keep the flames out of the chimney and try to retain as much heat as i can. i am not in a position to buy a new cat stove also i like the challenge. please elaborate on all thoughts and opinions on this topic. this is just a start so i will be working on a more detailed drawing(s). as i progress (with the help of the forum) i will post all pics and drawings for review. thanks for reading, please reply!

i just ran across this link: http://www.woodmanspartsplus.com/48...ombusters/Catalytic-Add--On-Stove-Damper.html

any users, suggestions? this looks like the best of both worlds.

based off of my neighbors carolina, he does not have any secondary controls. he has two primary dampers and two air wash dampers under the windows, to some those may considered secondary?? i to have 2 primary draft controls and 2 air wash dampers, with that said is there still concern for a secondary control to activate a cat? i have really only seen one cat stove operate and that was lastnight. it seemed like it was very easy to duplicate, his cat was on a slide inside the firebox. whenever you inspect or reload during operation you just pull a lever from the front of the stove and the cat is moved from the flu allowing the smoke to escape with no obstruction. i did have a concern that a "add on cat" would be too high, in other words i think it would be to far away not allowing it to get the temps it needs. i am just torn with what to do. now im leaning towards puting a cat on a slide.