Tecnoarm vs. modded Moth Mk. 3

I've been told that the Moth arm is based on the Rega 301, while the Tecnoarm is based on the Rega 250. Both arms are available with upgraded wiring (copper or silver litz), VTA adjuster and Michell technoweight. Pricing is comparable.

Is either arm superior to the other?

In my opinion the Rega 250 based arm (Technoarm) would have to be superior for 2 reasons.Firstly it is fixed to the plinth by a nut and not screwed on at 3 points like the RB 301 based arm (Moth) would be.This allows for tensioning the nut in the case of the RB 250 for fine-tuning the sound easily, which you cannot do with the 3 point system of the RB 301.Secondly there is the issue of the resonating spring in the RB 301's weight setting mechanism at the arm's pivot which is absent in the RB 250 based arm because they use a different mechanical design.Please correct me if I have missed something but I would go for the Technoarm because it would be less compromised soundwise.
I own the Michell Tecnoarm and I really like it alot.. great sounding arm for its price .. probably the best in this price/fascia
Thanks. I'll be upgrading from a Basik LV-X shortly. I was initally looking for an Ittok but now I'm leaning towards the Tecnoarm.