Does turntable/arm/cartridge count as "a component"?
If not, it would be the Pass X0.2 linestage. It's very comforting to have a preamp that inspires unconditional confidence in it regardless of system makeup or room placement. All else - amp, sources, speakers... can be plugged'n'played with that much more security in the perceived outcome.
Can I trade my ears for the Mk2 upgrade?
Aside to Bigfish8. The strategy that has worked for me is: First lay down the "backbone": pre and amp. Integrated, if you find a good'n. That way you can evaluate sources and speakers from a stable reference. When I upgraded recently (the story is in the "Our systems" thread) that's where I began. Now I'm finishing up source selection. Final duty, to be undertaken when my funds have recovered ... and when I have a better understanding of that can o'worms ... will be interconnects, speaker cable and AC power cords and conditioners. Spouse's incredulous reaction to last tactic can be seen under my identifier...
cheers ww