One of my pipes that I use most often is a pencil shank by Tom Eltang. Dublin style bowl. I suppose it is around a "group 2" or "group 1" size. Maybe between the two groups.
It lasts about a half hour, on average and it smokes very cool to my tastes. Perhaps the extended shank helps with this, but I'm not sure. The bowl stays cool/warm to the touch, but never hot.
I'm guessing similarly sized pipes will have similar results. No need to go get an Eltang, though the engineering on those pipes is fantastic.
Just hunt a similar shape/size. Excellent smokers if you don't want to spend an hour or more with your pipe. I don't think they smoke any different from my larger pipes, except time spent burning.