VPI Aries vs. VPI TNT III

MY TNT 3.5 (SME V arm) has never gone out of adjustment once I have set it. I have checked it at several month intervals over four years of use. Not once did I need to re-level the TNT or readjust the SME. Weird that my experience is so different from others in this regard.
The only part that I have had to be somewhat careful about is the tri-pulley unit sometimes moves if I have changed tone-arm cable or something. I have caused the pulley unit to shift (or the base to shift) in these cases; so, I don't consider this a TNT problem at all. Besides, a slight nudge of the pulley unit probably does nothing to hinder performance--unless the pulley shafts touch the TNT base, of course.
I find the TNT reassuringly stable and simple to use.

I know someone who had his TNT 3 upgraded to a TNT 5. He never mentions any adjustment problems. I will ask him specifically about the need to re-adjust next time I see him.

I had the Well Tempered (Classic) arm on a SOTA Sapphire a while back. A clever 'arm. The Morch UP4 is also a very, very good 'arm on the SOTA, BTW. In fact the Morch UP4 (with silver internal wiring) seems like a "sleeper" tone arm. For the money, it's hard to beat.