Monte,
If he's hunting the ocean beaches, an SMF with an 11" or larger coil is the ticket. But that's only if he hunts there enough to justify the expenditure. Scott posted he's been watching hoards of YouTube videos so he will be aware of the obvious choice there. Only question is whether he goes there enough or plans on making Salt Water Beach hunting a regular thing.
As for the rest of his detecting, his original post didn't have enough info on the type of hunting he had been doing, nor did it have a list of detectors he was already using that may be able to be 'improved upon' by newer technology
So, making a suggestion based on a complete lack of information would be of no true value to Scott above telling him my personal preferences. And, Scott doesn't know me from a hole in the wall, so I gonna say he couldn't care less of my personal preferences if they don't relate to his own hunting.

. That's why I didn't make a suggestion.
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Now, Scott has since posted much more information and his hunting is actually
very similar to mine. Shallow water (Fresh) combined with DEEP park hunting.
With this additional info, what do i have to offer Scott? Well, to start, I notice that Scott likes his T2's, which can be very deep detectors in lighter mineralized soils, and an Impact, which i am going to put in the similar category of the T2's. It is heavy when compared to the newer technology detectors, but that may or may not matter to Scott. And the Simplex which covers Water Duties.
First question I would asked Scott is whether he finds himself digging A LOT of deep rusty nails when he's in the park? And at what depth are his "deep keepers" coming from?
To some extent, we can find shallow stuff missed by previous detectorists. This just requires a small coil and a lot of patience and digging. My thoughts are that his park is likely to have targets deeper than that and those deeper targets are what he's after. A little coil isn't going to help with that.
The newer detectors I've been using have been unmasking from the ferrous and non-ferrous trash at deeper depths. This is where there is a separation in ability with the older detectors and new. The problem is this, let's say I recommend that Scott give a try to a new 800, 900, Deus or Deus 2 or even a Manticore. Since he doesn't have any of these types of detectors in his current group, he's going to have to learn an entire new platform. That's asking a lot of somebody. There is the Legend though, a platform he already knows from having the Impact and Simplex. Option there.
In my mind, I guess that is what Scott is going to need to decide for himself - is he willing to learn a new platform? I've been using the Equinox 800 for 5 years now and it is on my recommend list for the types of hunting Scott has been doing; shallow water, salt water beach, deep park. I've been lucky that I've not had leaking problems with mine like others have. I think the 900 and Manticore have improved on the housing and search rods as well as performance of the 800, based on early results. But these are 'early'. Folks are running out and buying them and as weather in North America starts swinging into Spring, we will see many more reports to give us a lot more data points upon which to base a decision. The Legend has been out for a good amount of time and Scott can look at Legend Reports to help his decision making.
I have the new Manticore, and my first couple trips have produced a Peace Dollar, Standing Liberty Quarter, Mercury Dime, sterling ring, a couple wheat cents, an old sales tax token, some junk jewelry as well as odds and ends from the swimmers of bygone eras. This hunt area is a little unique though where the targets are all DEEEEP, in the 10-12" range
and deeper. The Manticore is deeper than my 800 in this environment. And I like the housing and search rod better than the 800.
As for regular park areas, I'm still frozen here in Northern Utah and my Deep Park should be thawed in the new few weeks. I don't know yet how the Manticore does compared to my 800 in the park environment. I'm guessing that it will surpass it, but guessing and actual can be different and I would rather NOT assume especially when it comes to making a recommendation to somebody else. Andrew, from YouTubes Relics and Rings, has a 900, Deus 2 and Manticore and has been doing some testing out at the Salt Water Beach and in a local park he found that was thawed enough in a couple spots to hunt. That would be a good source to check for additional information.
That's about all i got. Congrats again on getting through your chemo.
UtahRich
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Just one more good target before I go.