Pauly, I prefer the UP-4 to the RS-A1 for 2 main reasons. The UP-4 has better extension and a fuller midrange compared to the RS-A1, which is also very very fiddly to setup properly.
However and despite the RS-A1 not sounding as good as the UP-4, the special thing about the RS-A1 compared to other tonearms is that it can be situated (almost) anywhere on a turntable plinth, without the need to drill a hole for mounting. Mine is currently installed onto the plinth of my Garrard 401, together with an Audiocraft AC-4400 and a SME 3012 II. I just use some blutack to secure the base to the plinth.
Dear Raul,
Unipivots have a special place in my collection because of what they do to the midrange on vocals ... they seem to my ears to make the voices sound natural, open and slightly more emphasised, compared to other designs, at the expense of some dynamics or extension.
Kind regards,
Anthony