I was looking into both of these for our trip to Norway this winter
http://www.arcticheroeschallenge.co.uk. I came up with all sorts of pros and cons but the biggest 2 were space and cost. In the end, as we weren't restricted by weight (we are driving up through Norway) we found and contacted Belltent.co.uk who offer cotton bell tents and they kindly agreed to sponsor us.
The model we chose was a 4 metre version with built in ground sheet. The space inside compared to the same height Helstra (which one of the other teams is using) is considerable, from the outside it doesnt look much but from inside its huge.
The other advantage is that you dont have to have the flue running up the centre. We chose to locate it inside the door to right, this allows us to access/tend the stove from the doorway without removing our boots.
Weve tested it several times, most recently on the Welsh coast in the heavy rain/storms we have 2 weeks ago and it was superb. Robust, dry inside, toasty with the stove and best of all, not flappy like most nylon versions.
One thing that was interesting was the trial and error involved in finding a good balance heating the stove - small wood warms the tent quickly but requires a lot of attention, long burn logs are good but it will need to get colder before we can test properly.
