Tonearm comparison, Rega vs Zeta, anyone?

Just a thought. The high mass Zeta may be a bit heavy for the Dyna 20, but the SME M2-9 would be a nice step up from the Rega, a good match for the cartridge from an effective mass standpoint and SME arms were commonly bundled with Oracles and are part of the design center of the turntable.

The Syrinx LE1 was the bottom of the Syrinx line, their offering in the "budget" arena, and unlike Rega they weren't geared up to mass-produce, crucial in that low-margin market. Quality control was all over the place.
I have and still use the better Syrinx PU3 and it's superb. It beat the SME 309 (IME) — the 309 is a pricey high-end arm — in a strict head-to-head comparison. And I didn't want it to, so there was no confirmation bias. It destroyed the RB300.
I've not heard the Zeta, but it was reputed to be competitive with the PU3, one the "super arms" UK seemed to produce in abundance during vinyl's so-called Golden Age.
Viridian's suggestion is a very good one, and he notes the Oracle/SME connection. SME made an arm specially for Oracle, though it was a variant of their TOTL V, as is the 309. Again, I've not heard the M2-9 but I've owned several SME arms and they never disappoint.

Early Zetas had bearing issues. If it is fine today, it should be fine tomorrow.

It was not all zetas, but a few, and of course it was blown out of proportion. They had excellent bearings with just the right amount of of play and tightness. Which means, depending on how the metals were stressed during cutting, shaping and finishing and usage/application, means they can either go loose -or go tight. IF lucky and well planned, they stay in the zone. EG, all Dual turntables of the 80’s require arm bearing adjustment. All. It was even an instruction set -- in their tech manuals.
Fix the arm bearings according to the manual on a $25 Dual belt/direct drive unit from the 80's.... and you've got  cheap performer - for peanuts.

The Zeta was always an excellent arm. Early Kuzma Stogi’s come in at nearly the same price and play in the same range of quality. A minor mod can make an original Stogi really step up to the plate. The original Stogi was designed principally on an LP12.

Just checked, maybe not.. getting rare and prices are going up.

Zeta it is, if the decision was mine.

We are talking about synergy..and I’ve owned the Delphi, a few times...and had a stogi on it. As well as an early Linn Basik Plus. Knowing the Zeta and what it was generally paired with (low output MC, mid/high mass suspended tables).... the Zeta should work decently on a Delphi.

Results will vary according to human tastes in listening, of course.

Edit: just remembering how the mat and clamp combination on the Delphi has a tendency to slightly over-damped, which darkens and slows things a bit and the high output dynavector should negate some of that, due to how high output coils tend to sound and how they retrieve signal. Might be a very nice combination.

You might find yourself staying there for a while, and not trying to visit anything else.....

If you try it and like it, and wish for just a hair more air, tightness, and speed..if you have the original acrylic arm board, switch to an aluminum or metal armboard.

if you still have the acrylic arm board go buy an aluminum one from oracle they are a huge step up and look way better too. and reasonably priced, get a service kit while your at it if it has not been done already.