What's the nature of the debris/gunk that came out during your first flush?
So initially I used Primochill Rad Clean in the radiator for 15 mins, then flushed, then 30 mins, then flushed, then an hour, then flushed, and then finally added the radiator to the loop, ran it for an hour with clean distilled, then drained it all out and replaced with Cryofuel. Probably a little excessive, but I'm pretty skeptical of offbrand China/Taobao items, so I figured why not.
The first flush produced green-colored fluid (the copper oxidation color or w/e) with a lot of black/copper-colored debris in it, and the subsequent flushes were mostly additional black debris (some definitely large enough to get stuck in the CPU block fins). Then the full drain of the Cryofuel after ~36 hours didn't produce anything notable (just 4-5 minor debris, likely tubing particles), and that process also included me disassembling the LT Solo to inspect for issues.
I've got Primochill System Reboot running thru it now, but at this point I'm assuming worst case scenario will just be that it comes back discolored when I drain it again later this week. Seems like the radiator is solid, it's just likely that they don't have clean procedures for painting/storing it.
And... uh... I also went ahead and picked up a 9900k (caught one sliding thru open box at Micro Center, so why not), and under the same clocks/voltage (5GHz core, 4.7 cache, no avx offset, 1.285v, R0 steppings; but 200W load instead of 180W), the rad only performs ~3.5C warmer than it does with the 9700K in P95 26.6. Obviously chip-to-chip temperatures can vary greatly, but this was a nice surprise given that the 9700k at the same wattage (5GHz at 1.315v I think) was performing much worse on the ST25 radiator.
