Question Should I avoid Quad Channel DDR5 (5600mhz)

[Gamefreaknet]

I have 2 options at current. Buy a 64GB (2x32GB) kit of RAM (more expensive but safer option from what I've read for performance) or risk it and get another 2x16GB kit to pair with my current 2x16 kit (which I know exact details of so I wont be mixing different RAM since I know that isn't recommended). Whilst I am fine to get the extra 2x16GB (if theres only going to be a minor/barely noticeable difference) how "tempermental" can a 4x16GB setup be at current?
Specs:
i7 13700K, 2x16GB 5600mhz (Crucial) RAM, 4070ti,

 

[Aeacus]

You will not get quad-channel with 4x sticks.

DDR5 is different than other RAMs before, whereby you'll have dual-channel even with 1x stick of RAM. This is so because in the single DDR5 RAM DIMM, there are two 32-bit memory channels (compared to e.g DDR4, which had one 64-bit memory channel in one DIMM).

So, in that sense, and IF the MoBo would support quad-channel RAM, you'd get quad-channel with only 2x sticks when using DDR5 RAM.
Now, consumer grade MoBos, even high-end ones (e.g Intel Z790 chipset or AMD X670E chipset), does not support quad-channel RAM, despite MoBo having 4 RAM slots.

Whilst I am fine to get the extra 2x16GB (if theres only going to be a minor/barely noticeable difference) how "tempermental" can a 4x16GB setup be at current?

Chances of getting two sets of 16GB working are 50:50. And chances that they all (4 sticks) work faster than JEDEC standard (4800 Mhz), are even smaller.

Further reading (especially mixed memory chapter),
link: https://forums.tomshardware.com/thr...y-ram-and-xmp-profile-configurations.3398926/

DDR3 was quite lenient and it was possible to mix different brand RAMs, even different amounts, resulting into obscure total RAM amount, e.g 12 GB (8 GB + 4 GB). DDR4 isn't that lenient and it is relatively rare to get two different RAM sets or sticks, to work together nicely. Even rarer to see them woking above JEDEC speeds. (Read the topic i linked.) DDR5 is even more capricious and chances would be slim to none.

If you want a guarantee that your RAM works at advertised speeds (faster than 4800 Mhz if you get e.g 5600 Mhz set), then buy the set and use only that RAM set. Do not mix memory.
But if you have money to waste, time to spend and patience to deal with RAM lottery, go with 2nd 2x 16GB set and prepare yourself for the ordeal to get all 4 sticks working nicely + getting them all working at 5600 Mhz. <- 0 guarantee with that.