Of all your gear, what piece impresses you most?

Well my 2 cents (a bit more than that...) - the 2 most important parts of an audio system is the source (and to be more precise the dac) and the speakers. Hence I will pick the dCS Vivaldi dac and the Vivid g3 speakers.

Maybe my choice is do to my other components or possibly the other way around but I would have to say my
Tron Syren Full Function Pre Amp.
In a word Fantastic !!!!

The gear that impresses me most is not necessarily also the most irreplaceable. There are many very good amps and power cables in the sea.......

The BSG QOL unit.
2nd place is the Synergistic Research HFT's.

I consider my system to be well balanced, however I consider my BEL 1001 MK V to be my most valued component. Probably most difficult to replace from either a sonic or cost basis.