I've never tested the draft, nor have I put a thermometer on the stove but I run pea in my Mk I all year. As long as the temp is above 30* or so, I run it at about 1/2 a turn and can keep my 1200sf house (one level) between 65*-72*. If it gets down around zero degrees, then I can open it up to around 1 1/2 turns, maybe two. At that point, I can only get about 6 hours out of the stove before I have to attend it vs. nearly 20hrs running it at 1/2 a turn.
If I run nut coal, and I did for about 2 years, I can't get it to "idle" to a comfortable heat level. It's either hot, or it's choked out dead.
I am, I guess, somewhat unconventional, but I run a manual damper that I fully close when I'm running it. I think I just have an extra strong draft or something. If I crack the damper at all, I get a runaway fire. Even though I only have the air adjustment open 1/2 a turn.