I second that. I only use X1Cs. Had a gen3, gen7 and currently use a gen9. The one I have now (X1C Gen9) is the first one that turns the fans on without any CPU

I second that. I only use X1Cs. Had a gen3, gen7 and currently use a gen9. The one I have now (X1C Gen9) is the first one that turns the fans on without any CPU heavy task (compiling, blender, stuff like that). Low RPM, but fanning nonetheless. I throttled the CPU (i7-1165G7@2.8GHz) to 2GHz (the hardware limit is 4.7GHz), and it no longer heats up; bullet dodged. The gen7 had a screen malfunction, repaired under warranty with flawless service. I just upgraded because it would take two weeks for service turnaround, and we might as well have a spare laptop around. Excellent keyboard, much better than Macs. I use trackpoint, so I'm unable to evaluate the trackpad. The internal display is 1920x1200, and I have nothing bad to say about it. Excellent linux driver coverage. Runs cool, even if it required capping its performance.