I've used Speer bullets for a long time, though over the last decade or two they've been largely supplanted by Nosler and Hornady. I still use Speer in two of my rifles, though. I use the 150gr Flat Point in my 30-30WCF, and I use the 220gr Flat Point in my 350RemMag. Both of these are the Hot-Cor design, where a molten lead core is poured into the formed copper cup, rather than a cast core being swaged in place. Supposedly, this cuts down on core separation, and is really the precursor to bonded bullets, in some ways. Based on the rifles I use these bullets in, I can't speak to whether or not the process helps with core separation, as neither is known to blow bullets apart. But both bullets expand well in game (based on wound channels and exits) and I've never lost a game animal or varmint I've shot with these bullets.