Quote Originally Posted by basite
I have a near 40 year old luxman here that measures better than my modern denon integrated amp... nothing has been done to it...

the only maintenance I did to it was use some deoxit on the potentiometers...
and the Marantz 22 series were very good made indeed, I'd prefer it over a modern HT amp in the league of that particular onkyo, even though it doesn't have a remote, the home theater features, ...
home theater features which of course, you'll only have benefit from when you actually have 5 speakers, but he'll start out with stereo speakers...

just saying, the onkyo will fall short sooner or later, it's not stable enough to drive 2 speakers with a 4 ohm impedance, or heavy impedance fluctuations, this all limits the choice for future upgrades.
on the other hand, the marantz, will offer you good sound, will drive speakers more easily, will have a better phono stage, and, if you decide to upgrade, you can sell it for the same money or even more than you originally bought it for, while you'll have a hard time trying to do the same with the onkyo, if you can sell it for a decent price, that is...

about the "which will run longer", it's a speculation indeed, but in all honesty, I'd more trust a well made vintage receiver than a cheap modern amp. but of course, I had bad experiences with that already, so I might be biased...
If I had to choose between the Marantz being better made or having every other advantage, I'll choose every other advantage. And I have nothing against vintage receivers. I still frequently use my Marantz 2325. But if I were just starting out, and I have the OP's current gear, there's no way I would spend my first money on a 35-year-old 2-channel receiver and live without all those other features.