EDIT: little updates here and there to make my point clearer.

I am not sure where your question comes from.
Do you own the ADI-2 Pro ? Do you know how it sounds ? Are you satisfied / dissatisfied with it ?
Or are you simply worried not getting a product which is not on rank#1 of Audio Sciencereview ?

My impression of audiosciencereview is that their strong focus is measuring and interpreting measuring as good as they can. What I am missing there is a discussion of the relevance of the measures regarding, whether you can actually hear a difference when you use the devices.

When I am driving a car, I have requirements. Speed, acceleration, comfort, ... How the manufacturer achieves this, doesn't matter much to me.

When I get an ADDA converter, DAC, etc like the ADI-2 Pro I am of course also interested into technical data. But I want simply ensure that SNR and all this stuff is "on par" or better than other devices as of 2018 (what electronic curcuits are usually able to deliver). Also the price needs somehow to fit.

But at the end of the day its for me more important, how it sounds.

So .. I compared the Accuphase DAC-40 module of an E-600 Class A Amplifier with B&W803D3 speakers against ADI-2 Pro (DAC is the same soundwise). The result for me is, that the RME ADI-2 Pro delivers a little bit more detailed/precise room information/definition and maybe a little bit more defined sound character. Sometimes I had the feeling the ADI-2 Pro in NOS mode sounded more like the DAC-40. The differences are only very small, you need to be very concentrated when performing this A/B comparison and need to repeat this with fresh ears.

This is what counts for me, what the product delivers in daily use. So if the ADI-2 Pro sounds better than the DAC module of an High-End HiFi amplifier, then I am really satisfied with the ADI-2 Pro / * as it offers even much more (many benefits and features, see handbook). If I would have known this before, I wouldn't have bought the Accuphase DAC-40. On the other hand it was an interesting experience.

Especially if you look, how many features RME bundles with these products, which is definitively NOT the case for all the other "Top-5" devices in Audiosciencereview, that you mentioned, then I can only say that I am really satisfied with this product, even if it doesnt have the latest and greates chip inside. As you said, RME made the most out of it.

Well, I wouldn't be frightened to buy these RME devices now, because they are an excellent masterpice of engineering and offer the best value for the customer.

OK, what if RME would use the other components ? Maybe the measuring results now get slightly better, but is the difference really remarkable enough ? Does this alone justify the surely higher price ? Does this give the customer a real value ? Maybe its much better that you get excellent quality to a real fair price, considering what quality RME gets out of the current chip and what features come bundled with this device as of today.

Just my $0.02 when reading questions like this.

If this is the case yes I would think so.

Thats what I also think. The Accuphase DAC-50 board (newer model) currently costs €1250 alone and I think the DAC-40 wasn't cheaper.

And if you read this test the magazine .. They compared the built-in Accuphase DAC-40 module against the Accuphase DAC standalone unit - DP-550 – which costs €10450. There wasn't much of a difference. They said both played on par. The mids were with the DAC-40 a little bit more distinctive, whereas the DP-550 sounded more smooth (or flat?) and relaxed. Only very little difference but compare the price, factor 8.3.
Maybe its even only a matter of taste and what amp / speaker combination you connect to it, whether you prefer the one or the other.

So I regard it as questionable to focus only on numbers. There are also other factors which bring sound and quality.
The design of the PCB, where you place what components, programming, etc.

The last firmware upgrade even reduced the inaudible ripple, nice for measuring, but inaudible.