I use a Pimax 5K+ with iRacing now and recently received my 8KX. Here is a rig workshop stream going through the software and hardware setup.
My 5K+ has been running on a really old PiTool version 144, so I first wanted to go through updating the Nvidia GeForce drivers and PiTool to the current versions making sure at each step that the 5K+ was still working okay.
Then we transition to the 8KX and initial impressions.
If you are actually interested, it may be best to open the video on the YouTube website to see the direct links to each section in the video description.
https://www.youtube.com/watch?v=d6_igUHaGck
0:00:10 Starting with new Nvidia GeForce Driver v456.38
0:04:30 Testing those new drivers in iRacing - looks good
0:07:36 1st look 8KX in the box!
0:08:15 Concerns about the head strap hinge limited angle/range of motion
0:10:50 Update PiTool software to v263 - big jump from v144
0:13:28 Save test pattern cross hatch image for IPD/alignment adjustments
0:28:45 Sensor detection abnormal on 5K+ with v263
0:32:58 Firmware update on 5K+ - needed to disconnect USB while PiTool was running
0:36:15 All is well with the 5K+ on v263 with the new firmware - PiTool options setup
0:45:45 Test in iRacing with 5K+ on new GeForce drivers and PiTool. Seems good
0:51:05 Check screenshots to compare resolutions - they are different 4268x2784 (old) vs 3412x2228 (new)
0:56:00 Test again in iRacing with similar resolution: 4264x2780 as close as it gets. Still good
0:59:13 Long distance (40ft+) cable run woes
1:00:57 First time 8KX startup
1:06:05 SDE? Not really
1:08:56 Test pattern startup image replacement and IPD/vertical adjustment overview
1:12:30 8KX in iRacing for the first time - resolution still set at 158% form 5K+
1:16:23 OMG moment
1:19:45 Crazy resolution zoom out 6268x4172
1:21:20 Try at SteamVR “recommended” resolution - pretty low - 3820x2544
1:28:30 Try at SteamVR 100% - 5020x3340
1:32:05 First notice of eye comfort concerns