Cary, Cayin or Primaluna EL34 for Merlin VSM-MME

I'm looking for an amp or my Merlin VSM-MME speakers. I know it's been asked many times before, and I've read most of the threads out there. The consensus seems to be that an EL34 based tube integrated is the best choice. Unfortunately the Ars-Sonum is out of my price range. I’ve got three amps that seem very similar on my radar and I’m looking for any opinions, comparisons, or/and criticisms.

1) Cary SLI50
2) Primaluna Prologue One
3) Cayin A50T

All are around $1000 used and have enough power.
Cayin, great sound, great value. Keep in mind that Primalune and Cayin are essentially the same unit.
I think you'd do well to try to audition a Manley Stingray integrated. I think that you could find one used close to your price range.
I second the Stingray recommendation for Merlins. But EL34 in general is the way I would go rather than 6550/KT88 - at least with the VSMs, and I would think the TSMs as well, but I would discuss it with Bobby P (Mr. Merlin) - he knows his speaker well.
Primaluna has the advantage of continuous autobias. There's no need to ever bias the power tubes, match tubes, or wonder if you're getting the best out of your amp.

The power tubes are always running in their sweet spot so they should last longer as well.
Autobias is really nice, but best sound is better. Not saying the Cayin's don't sound better, but just priority. I notice that some of the very expensive tube amps, let's say CAT JL2/3s don't use autobias, and if I know Ken, it has something to do with best performance - but I do appreciate the feeling of knowing the bias is being managed, on the other hand, setting bias manually and seeing it stay there has its own satisfactions.
I have the Cayin and am very impresed in the sound for the price. Clean and clear, resolving, holographic image, emotial impact, natural - albeit it not eternal but natural decay and great soundstage and placement of instruments). I guess I should check bias soon but over a year (PC system so light use) it still sounds spot on. Anyone know of probes that fit the Cayin A50T? I have stock probes on my Simpson VOM and they are too short (standard length-the Cayin needs something different). I have beem twisting silver paper clips around the probes to get the extension but willing to pay some bucks to get something that I don't need to jerryrig.
The Cary is the only one that is operating in class A. It is also made in America. This amp is truly special with the right speakers. I have not heard the Cayin or the Primaluna but can say the Cary handily beats the Stingray.
@Buconero117: The current Cayin amplifiers have nothing in common with PrimaLuna, other than both being built in China. PrimaLunas have different chassis designs, different circuits, different transformers, different parts, different quality control oversight. While early Cayin amps shared a similar chassis with PrimaLuna, Cayin no longer makes those amps.

@Pubul57: The Adaptive AutoBias circuit in PrimaLuna amps is an extremely sophistocated circuit that constantly monitors and adjusts bias according to operating variables inside the amp. It's not just a simple cathode-bias circuit found in the majority of "auto-biasing" tube amps, which can hinder sound quality.

Bias fluctuates during listening, depending on a number of variables. These flucuations can negatively impact sound quality as the bias drifts away from the optimal setting for the amp. Adaptive AutoBias monitors these changes and adjusts each individual tube according to its needs, ensuring all 4 tubes are always operating at peak efficiency.

A reviewer in England compared two identical PrimaLuna amps, one with Adaptive AutoBias, the other with manual bias, and noticed the unit with Adaptive AutoBias had dramatically better sound quality.

Can you please close up with our deal which I RETURNED your amp and waiting for your refund?

Thank you,

Thanks Carter for responding finally and squaring the deal right and well. Thank you and apologize for the interruption on this thread.
Bit out of topic, but...

I own PrimaLuna Prologue Two and that's a very good amp, especially when you tune the sound with valves to your liking, which are endless to choose from. I would go for Two instead of One, cos, jumping from EL34 to KT88 is not the same as from KT88 to EL34, however I will know this for sure when my EL34 arrives.
At the moment I wait for some NOS EL34 Telsa's, not JJ, but the real one from 1970-80's, and I expect some nice changes from already brilliant NOS GEC KT88.
I run it with Sonus Faber monitors, great match, but my surround Canton CD100 speakers become a huge surprise as well, just don't believe they sound that good.