My buddy Dale runs a older Okuma lathe at a shop down in Ceres and he had the same deal go wrong on him. He kept the override pinned at 125% for months on 4140 and could not figure out why his insert costs were eating his bonus, then one day his setup guy watched him run a part and told him he was basically burning the coating off on the first bite. Dale started leaving it at 85% until the spindle load leveled out, then easing it up maybe 5% at a time, and he swears his corners last almost three times as long now. He told me the sound is the giveaway for him, once that chatter goes away he knows the cut settled in and he can push it. What he does not mess with is the finish pass, he leaves that alone no matter what.

The "search YouTube reviews instead of Amazon listings" thing is exactly what saved me too, but my twist was hitting the ham radio forums before buying anything. I found a thread where a guy in Ohio posted his actual nighttime recordings from three different receivers on the same longwire, and you could hear the difference plain as day. Amazon reviews are useless for radios because half of them are from people who never even hooked up an antenna, they just think the box looks nice. That forum thread steered me away from a $120 set that everyone on Amazon loved and toward a used one for $50 that actually holds a signal. Steve sounds like he knows his stuff, listen to him.