If you have a smaller tent, then go with the next model down. You wont regret it.
Thing I actually miss is the prep work...chores each mid day...chopping wood, stockpile along front and side wall of the tent. This helps reflect the heat inside the tent. Some of the "NEW" guys in our hunting group dont know what it was like for prep work each day in camp.
The temp on our heater was as low as it goes and we slowed the fuel rate down as low as we could. Lets still say I slept on top my sleeping bag most of the time........even debating this year moving to the front side of the tent. Only thing is when my kids start wanting to come out, it will be nice to be in "My Stall" for the cot for them. For an estimated temp....15 to 20 maybe. We never really checked. We have a MAX/MIN temp gauge outside hanging near our cookshack to monitor the temp. May bring another to chech the tent temp for something to do.
Our shower setup is maybe 5-8 metres from the camp. On cool or cold days its a fast run into the tent after you dry off as much as you can to stay warm and get dressed. We heat water in SS pails on the firepit, dump into a 5 gal pail, mix with some cold water for the right temperature, and use a small submersable pump with a hose hooked on with the Kitchen sink style spray nozzle. WORKS AWESOME!!
We use to frame up a small area and staple thin poly to the frame. Use to suck when the wind picked up and shook al the cold water droplets on you. Now we have an actual outside portable shower frame/setup. we stand on a plastic pallet that lets the water fall thru.
Its nice to be refreshed after 2-3 days being out hunting....sometimes 2 showers in the week at camp.