SME IV.Vi or V tonearm: different internal wiring

Actually, I would never think of tampering with the arm myself. If something has to be done, it will be taken care of by someone who's in the business of dealing with rewiring arms. I've also had both the V and IV.Vi, and like you, have preferred the sound of the IV.Vi, probably in part because of the Magnan Vi wire inside. The Vs have been factory wired typically with Van Den Hul, which, based on what I've gathered so far from comments of some of the others who have owned it, is not exactly the "cat's meow".

So that there is no misunderstanding, my comment above refers specifically to the Van Den Hul internal wiring and not the SME V arm itself.

To my ears, the Magnan Vi wire inside the SME IV.Vi offers more top end extension in contrast to the Van Den Hul wire found in the SME V. I also feel it helps provide a better balanced sound top to bottom. I'm ignorant, however, as to whether or not the V's damping mechanism contributes to any significant sound impovement relative to the IV.Vi in standard form without damping. You also advise a better phono or tonearm cable. I'm extremely pleased with my Purist Proteus Provectus tc. Regarding the idea that SME would best be suited to do a rewiring, I was told by someone at Sumiko(who imports the SME arms)that SME undertakes a thorough job with checking, refurbishing and replacing parts if necessary in addition to rewiring the arm, and that the total cost for this is...I won't mention the figure...what I feel,obscene. Besides, there are quite a few positive feedbacks here on Audiogon for at least two services that offer to rewire SME arms at a "slightly" better cost.

As of 2007, SME uses the Van den Hul monocrystal silver inside the V tonearm. One Audiogoner(Clabe)who had his V rewired by SME did not care for its sound, so undertook on his own the job of replacing it with Magnan Vi, and was very pleased with the result. If I was in your position, I would keep the V. It is an excellent arm. But, it's obviously your call. Like me, you might try to gather some information about other brands(Cardas, Discovery, Kondo silver,etc.)of internal tonearm wire before making any kind of move.