Vintage Amps - Pleasantly surprised

A while back, i was given a non-functional Sansui AU-666, which I recently had restored for sh*ts and giggles. Hooked it up to Rega Aras in my bedroom, using a computer source with a basic NuForce uDac.

Honestly, i was not expecting much out of this combo. However, I am blown away by the sound quality i'm getting out of this extremely modest setup. It shockingly possesses much of the desirable 'audiophile traits' one would typically hope for. I'm not saying it's perfect, but for a 40 year old piece, i'm utterly stunned.

And considering the entire setup cost less than 450 bucks, including stands (excluding computer, but which i had already), i could not have asked for more.

Anyone else with this kind of experience using vintage gear?