I say yes, and this is why. When I started the hobby about 6 or 7 years ago I found that most of the "good" and obvious areas for older silver were really cleaned out and there wasn't much left. I haven't used an ACE 350, but I've used many other Garretts and the sniper coil will help you get to those older silver coins in trashy areas where many people avoid. Go slow and pick your way through, don't be afraid to dig some junk along the way and I bet the rewards will start to show. Hunting this way generally means your junk to good target ratio is higher, but I don't get too concerned about how many coins I put into my pouch if a couple of them are oldies. Most good ground has seen many coils, you have to hunt it differently than everyone else if you expect better results. Good luck in your search!
Craig