The gas leaving the stovepipe needs to have a certain temperature to be able to heat the chimney to actually create proper airflow by thermal venting.
The pipes you are linking to are actually meant to insulate the pipe, making it cooler on the outside, the gasses hotter, allowing the chimney to get hotter and generate more updraft, pulling more air into the stove, burning more wood, making more warmth.
Of course you can overdo this and have too much heat escaping as hot air. This is why the kind of stove, length of stovepipe and kind of chimney have an influence on the efficiency of the whole system.
If you have good draft, you might be able to extract some additional heat from the gas. If not, you may be able to profit from insulating the pipe to increase draft.
All this of course means you have to let air into the house from outside. If your house is new and well-built, it may be too tight to heat with wood. Try if your oven works better if you open a window slightly.
Also, dont mess with your stove without knowing what you do, or asking a professional. After all, you are dealing with a column of flame passing through your house.