I did, actually!-) The build is not really about looks, it's about performance. I think it's common sense that the tubes should be down as air goes to the top and so stays out of the circulation, that was not difficult to decide as there is space for this configuration too.
What I did consider carefully was the radiator placement front or top, but here I trusted GN tests showing that front is the best location. The 3080 produces so much heat that getting it our of the case is the number one priority. It seems better to let slightly more warm air into the case through the front front rad rather than pulling the very warm graphics card heated air through a top placed rad. The GN numbers for front vs top placement showed a significant difference.
I guess the "on topic" thing here would be the 3080 (and 3090) heat production, you really need to consider it when building a system around one.
I beg to differ on the front placement of the radiator.
The hoses being on the bottom are a good start but since hot air rises, you want the radiator at the top.
For maximum efficiency on any radiator, you'd want it to 'wick' heat into the fins and then fans to carry that heat away in as short a period as possible.
You also want it to carry that heat away in the direction which is most conducive to it's normal path of travel.
That's up...in the case of heat.
You are probably asking... Why then don't automotive manufacturer's do just that?
The answer... It is a 'liveable' trade-off.
The space required would be much higher...as would your hood-line.
That'd lead to less efficiency...not to mention, you'd need a perforated hood.
They instead use plastics under the engine compartment to protect from superficial damage but more importantly, to generate a low pressure area to act as a scupper/diverter.
That hot air then goes from high pressure to low pressure and is sucked out the bottom of your engine compartment.
Getting back to your install... The air movement from your fans...even if being pulled through the radiator, will be dumping hot air over components before being exhausted.
It won't overheat though because you are still moving air as a cooling media but it won't be quite as efficient.
On the reverse.... If they're pushing air the other way, there is still an influence on the case internals because the rear fan will pull some through.
At the top of the case it is a 'free' ride away.
We use these method all the time for cooling P3 air by routing to pre-cooler in jet aircraft.
We can drop 400 degree compressed air down for things like wing anti-ice, cabin bleeds, ejectors etc...
Airflow is fun to study and implement.