I am torn between a Dickson P9000 or a propex HS2211 and mounting it externally in a box like erstwils did.Very intrested in your build. Am working through the same project. Did one up in the 6 foot version but ended up selling to start again with an 8 foot. Did you decide on a heater?
Dickenson: looks great and doesn't require any power to run (without fan) however it takes up room inside
Propex: big pro of this is that it has a thermostat. Also can be mounted externally to save room. However, I heard that in order to preform well at high altitude you need to buy an additional kit. Also I heard they're no super quiet.
The one thing holding me back from buying the dickinson is that it doesn't have a thermostat. I am kind of worried that it will put off too much heat that I'll have to turn it on and off every hour to keep the kap at a comfortable temp.