The longest you have owned any gear?

Pioneer SC-700 preamp and Sony TA-3200F power amp, both bought in 1973, both still in operation.

Air Tight ATM3 since 1996.still in use today. One of the mono bloc has been for repair 2 years ago (timer for tempo needed to be fixed). 
Too bad 😀

Silverline Sonatina speakers. 14th year. Still sounding great. I replaced the binding posts after lengthy phone call with owner Alan Yun. Great guy to work with.

I have a BT-1 preamp, EQ-1 RIAA equalizer, and 50 watt AMP-1 still in use from 1974. All built by the Quintessence Group from Sacramento.  I switch the preamp out with a BT-2 from Audionics of Oregon circa 1980, still sweet!  The EQ is especially useful as it was designed around the inflection points on the RIAA record curve.  They  are in use in my office system, main system is newer stuff.

Limiting this to items that are "team 1 starters":
Rogue Hera preamplifier (now at Hera II status) - almost 9 years now, which seems like an eternity here; I’ve only been seriously at the 2ch game for about 12 years. Next closest would be a Koetsu Onyx at 6 years, which I’ve had recently rebuilt (though technically this now sits behind my new Coralstone).

I’ve tried to upgrade away from the Hera twice now -- both times to more expensive and highly review/regarded tube units from more prestigious hifi companies ($10K and $14K list prices) -- and both times I ended up going back to the Hera as my preference (though it’s not without flaws). The Hera was my first true "high-end" 2ch component, and perhaps part of my preference is that its sound truly has become my reference over the years. Maybe I’ll try to upgrade from it again in a couple years, but it’s been a real warrior for me!