Ahh so glad you could give us the 'inside track' Shaun. Just a shame it lacks a few pertinent points.
Patently you have made up your mind. That is fine. It's just a shame that bias of one form or another is clouding your ability to advise others.
I'll answer your points if I may.
1 - hotun had different models from day one.
2 - like every new product development continues no matter what. That some stuff went down is well known. Whether that influenced development only its MD can answer. To 'decide' here and now based upon nothing more than supposition is at best flawed.
3 - once again I am so pleased you are able to give us the benefit of your in depth and confidential communications with manufacturers. It's just a shame you didn't speak to those actually involved. I KNOW they have tested it, I've seen the videos.
4 - ahh I forgot. You are endowed with super powers. The diagnosis I refer to is where a slight discharge happens. With all others they often dry out as each drip runs past where it can be seen/felt. Due to hotun's design that gets caught and pools until there is enough to load the spring and let it pass.
Please enlighten me Shaun. Are you telling us here that nearly 100,000 buyers of hotun are stupid? Are you telling us that 4000 (growing) people per month are incompetent? Are you telling us here that PlumbCentre, Plumbase, Travis Perkins, Grahams and just about every other merchant in the UK are idiots too?
Oh and lastly, before you ban me from this forum for ever, are you telling me that the UK's NSF testing house (WRAS etc) are idiots and can't do their job? Obviously they must be as they have passed hotun for both WRAS and flow rates under frankly ludicrous fault conditions.
One a personal level, I am shocked by your behaviour here. I expected more of a person responsible for such a well run and objective site offering advice and guidance. Whilst we all have our 'pets', one has to walk the walk when you're the boss.