@alan60 I use a Tonearm design that as a end product is a not too common design encountered.
I have always sought out opportunities to experience devices in use, and have learnt over the years some devices are able to really impress.
Your very clearly made known liking for the the Viv Labs Tonearm, along with the the assessment, being it has proven for yourself, to be a more attractive arm in use that the ones you have mentioned, is quite a parallel with my own experience of a different Tonearm.
I have no longer any real intention to use the owned Tonearm Brands such as SME IV, or AudioMods Series Five.
Additionally after demonstrations, I know others who have departed from much more valuable Tonearms than the ones I have owned to give the priority place in the system to the same arm I am now using.
There are on occasions, a discovery made, that are requiring a ' Sat in Front Off' experience only, no amount of discussion (non experience) is able to show how the extremely positive impression is able to be made, and is able to impact on a person, changing with immediacy their long held views on what is right devices for themselves.