Flame guns??

Does anyone have experience of using flame guns for weeding please?
I've seen 2 different types - Sheen, running on paraffin (kerosene), and one running on bottled propane gas.
Any thoughts on whether they are a good idea, and if so which is best?

We have large areas of gravel driveway to keep clear, and also I'd like to use in the veggie garden if they work well there...

We tried a propane kind in the gravel paths in the kitchen garden and it was far too time consuming. Plus I burned myself very badly because the rocks transfer heat across themselves.

Now I use a Wolf Garten double edged attachment on the long handle and just push it under the gravel about once every couple of weeks. It cuts the weeds right above the ground and leaves the gravel in place. Yep- the weeds will come back but it is fast and safe.

Thanks daisy
I wonder if anyone else has had similar experiences, or do you all like them?