Our alcohol stove isn't pressurized and we like it. Propane scares me a bit on a boat. We leave our blower running whenever the propane heater is on.
We seem to have less condensation with electric than when we have to do propane. We examined all the heaters and their strengths and weaknesses and determined a 1250/1500 radiant heater was best for our needs. Works very good down to about the mid 20's and then we have to pull out the propane heater.
both propane and alcohol give off a LOT of moisture when they burn so they cause a lot of condensation issues. Best thing for condensation is hot air and or ventilation. Especially when it gets well below freezing as most of the moisture is out of the air, so if you can circulate some air, you loose heat but as long as it is being replaced with dry heat it will help.