The Platypus isn't going to give him any advantage over the stock coil in terms of finding targets in areas he's already hunted with the stock coil.
With the WOT he can start over in these areas and hunt a layer at least 2 inches deeper than he's been able to reach before, if coins are down there he'll get them.
Also, you CAN use this big coil in urban areas e.g. trash/iron filled parks, many of us have done just that with good results. Its more effort than using the stock coil, but if there are deeper targets in his area it will be worth it. The WOT has some interesting abilities to reach under the more shallow trash layer and lock onto deep targets, its also king for on edge coins.
Can you use a WOT in a trash heap nightmare? Well its not fun and you won't want to do that often but yes, if you go slow and notch out a bunch of the trash you can pick off deeper coins even in that mess. I have used the WOT at two such sites, one a field where they held large concerts in modern times and that place is a trash heap. Another was next to a baseball diamond where the fans stood, that also was a trash nightmare. The WOT was able to reach between 2 bottlecaps and lock onto a walking half dollar near that baseball diamond, I cut one cap in half cutting the plug and the other was in the plug, the silver half was under both. Moving the coil slow you could hear it hit each alum bottlecap, but inbetween the silver half was screaming silver through the headphones. Thats another thing about the WOT, you have not heard a silver hit until you hear one using the WOT, it screams when it gets over silver.
It sounds incredible I know but that WOT coil is spooky good.