I have RayDAT, UFX, UFX+, tested HDSPe MADI FX.
RME driver have all very similar very good performance in terms of RTL (Round Trip Latency).
See tabular of one of my blog articles:
> 1. does the newer AIO PRO have lower latency?
Depends on what latency you mean ..
- the RTL will be the same over PCIe as they use the same driver
- in terms of converter speed, well as I said, the RayDAT has no converters, its a full digital cards
> 2. Is it more stable at reduced buffer sizes?
They use the same driver. RME drivers are very robust with excellent performance. There are of course always a few systems which might have issues, but this lies in the nature of PC/OS design (BIOS, drivers, mainboard design, ..) and is not a flaw of the RME card.
> 3. I also think i read the RAYDAT does NOT have effects, even though it has the TotalMix FX software ( i guess it can only be used for routing purposes)
"TotalMix FX" is simply the successor of the older "TotalMix" Software.
The "FX" in the name is not related to FX effects on the card or recording interface.
Some cards have a FX chip, some not, it does not depend on TotalMix FX, it depends whether a FX chip is present on a RME recording interface. Some USB based recording interface have such a chip, some not. In the area of PCI/PCIe cards only the HDSPe MADI FX card has such a FX chip, all other PCI/PCIe cards not.
AIO and RayDAT do not have FX chip on board.
> Technically since all I need is small amount of ADAT channels, either card will work, just trying to see
> if any advantage going with the newer technology
This doesn't matter for the RayDAT as this is a fully digital card without any AD/DA converter.
The advantage of the RayDAT is, that you have other ports, that might be useful for you
and it has the possibility to add an optional Word Clock module.
As I said, look at the I/O ports to get a feeling, what gives you the best advantages.
I personally think that the RayDAT has many advantages and can be expanded very well.
BUT ... you need to add analog I/O first for your monitors and phones.
A very nice combination is: RayDAT, ADI-2 Pro FS R BE, ARC USB.
The new AIO is surely a very nice card, but it is missing a few features that the RayDAT has, i.e. Word Clock and maybe some other I/O ports, you should compare on your own please ! The information is there in manuals and on the webpage, you only need to read and "digest" it.
X10SRi-F, E5-1650v4, Win10Pro21H1, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT