You are correct that the smaller coil is better for separating out targets in trashy areas. Another advantage is more concise sounds and response (the larger coil can give "fishier" sounds as it is "seeing" more of the ground at a time, in its scope of view). The downside is, smaller coils don't go as deep as bigger coils. So it's a trade-off of benefits. I would start with the small coil first, to get used to the more concise separated sounds. Go to an area that's not too junky, yet teaming with clad. Dig 100 clad signals, get used to the sounds, and
then progress to deeper targets, iffier signals, etc... To start off by thinking you are going to master the fabled deep silver signals people talk about, while never having "paid your dues" and digging hundreds of clad, and hundreds of junk, just aint gonna happen.
Once you've got the various shallow signals imbedded in your brain, a way to help transition into the deeper "tooty fluty", is to team up with a proficient user (not just a sandbox hunter, but someone who routinely comes in with deepies/oldies from the turf), and have them flag some suspected deep coins. Watch the way they swing, listen to what they're trying to isolate, try to discern the difference between those signals, and ones they say they'd "pass". After having a few of these pointed out, the lights will "go on" and you'll be hooked
