That would depend in large part on whether they're wired to look at members of other sapient races as rivals for dominance, or as prey that fights back. If the former, yeah, they would tend to accept surrender pretty readily; if the latter, they might be biting out the person's throat before even registering that they were trying to surrender. Could play out either way.That's an interesting take on it.
Strategically, this is an advantage for them. They'll almost always accept surrender, and everyone knows it. Which makes it really hard to get your soldiers to fight to the death against them, when instead they can throw down their arms and live.