What issues are there with long USB cables?

[Quartz]

I've been very pleased with my fibre-optic Displayport cable and it occurs to me that by using long cables I could put my PC a lot farther away (cable-length-wise) and thereby reduce noise. The basic idea would be to have fibre DP cables going to my monitors and one 5m USB 2 cable going to a USB 2 hub and one 5m USB 3.0 cable going to a USB 3.0 hub.

I don't have any USB 3.1 / 3.2 peripherals.

Of which issues should I be aware?

 

[Quartz]

The expense would be considerable - the Displayport cables are £179 each. Plus tax. (And if you think that's expensive, take a gander at USB 3.x fibre cables.) So I'm looking at a bill of ~£400. Thus I'm trying to do some research first!

Anything that draws power will create more issues as longer wires will have a greater voltage drop and so eventual latency.

Both USB 2 and USB 3 cables will go from the PC to powered hubs.

 

[Quartz]

And I'm going to have to buy a long TOSLINK cable for my headset too.

Hmm... how much bandwidth am I going to need? Going through USB 2 I'll have a max of keyboard, trackball, headset, and HOTAS. I'll keep USB 3 for my phone and any external HDD.