I did look at those but decided against it for a few reasons.
It has two knobs to twiddle to get a decent flame....twice the workload.
It requires two gas bottles, one of which would probably be only available from a bespoke supplier and costly to boot.
Third and probably most important, it's made in China, you'd have to be bonkers to connect something like that to two bottles of highly explosive gasses in a domestic environment. There are two items you never buy from China, three actually, Batteries, things that make fire and electrical goods...the latter often doing the former all by it's self!
None are conducive to your health or well being.
Fourth, if it looks too good to be true, it probably is
I have a Proxxon blow torch and it's fine for larger work, I have an even bigger plumbers blow torch for domestic pipework attached to a butane bottle and never had to use it as yet, except for plumbing work, it's excellent for that
I did have a cheap ebay mini torch before, like others I've read about, it turned into a flaming hand grenade one day; luckily I was lighting the wood burner so quickly threw it in there, closed the door, put a large piece of wood in front of the glass door and waited until all the gas had burnt off from the leaks.
These look handy but I'm just wary that any that might be respectable and probably double the price from a 'UK supplier' are probably from China and having the price ramped up.
The HHO welder is more appealing, for starters there's no gas bottles lurking around, it's single valve operation so easier to use. But once again you're looking at a Chinese made model for economy, which is electrical and makes fire