To answer your question about the Omega/F5 and deeper coins, yes I think they go slightly deeper on silver coins.In a super trashy site there are other detector characteristics to consider though.
I checked your settings and although some say the G2/F19 will not lose depth with discrimination up, I have my doubts. If you are looking for deep coins mainly, I would only use discrimination at zero. I've never used discrimination past zero on mine at all and I've hunted mega trashy sites with lots of success (old silver coins and relics below recent clad, foil wrappers,pull tabs, iron bits and bobbles, etc.) By setting your volume at 10, you at least eliminate most if not all iron targets. Then you can set v-break at a numerical value higher than 40 to transfer the good signals of the VCO to an iron grunt. If you set your v-break at 60 for example, every target past 40 will give you the grunt of iron and everything else will give you the distinctive duck quacking noise of the VCO.
I find it essential to use good headphones with the G2/F19. The signal gets fainter as depth of target increases so you really need to hear the fainter sounds the VCO can yield. The volume of smaller deeper targets past 5 or 6 inches really goes down fast. Only the shallow coin sized targets are really loud (2-3 inches) .