I have perhaps a dozen "advanced" loading books, including Glen's. Different strokes for different folks? He's a knowledgable shooter and loader but also a college professsor; that means he loves the sound of his own voice! I had to force myself to comb through all the pages of chatty chaff to sift out the occasional kernel of hard info. And, as it's name suggests, it's directly written for those few of us who shoot competition, mostly large volumes of ammo fired in gas guns. That ain't me. Glad I have it but if I lost it I sure wouldn't pay for it again!
The "Precision Shooting Reloading Guide", edited by Dave Brennan, is much the best of any advance loading book I've ever seen. Well written, straight to the point info organized in eight sections, each written by a recognised expert in that area. It's half the size of Glen's book but has much more helpful info and it's less costly too. Sinclair International sells it, MidwayUSA has had it, maybe still does. If I lose this one, I WILL get another!