Mostly the promise that they do mostly the same, but vm uses less resources. I believe vm has slightly less resolution/fidelity - but not so much that we expect it to matter for our use-case.
But we're still implementing it - so we might still run into surprises.
Jan-Philip from Opstrace here, good morning. Would love to hear more, after all, when you know more :-). By the way, we had been asked about VictoriaMetrics before, here: https://github.com/opstrace/opstrace/discussions/98.
But we're still implementing it - so we might still run into surprises.