I tried a lot of these same pickups in my Mayones Regius and you might want to read my long thread about them.
Anyway I personally love Suhr pickups and can compare them. The SSH+ is definitely hotter than the Holydiver to me, and perhaps a little tighter in the bass (not that the Holydiver is loose at all). The Holydiver has more mids for sure, and more low-mids, whereas the SSH+ is a little more even in EQ and has more of those upper mids and highs to cut a bit more. The Holydiver can still cut on leads though, and the notes are a little fatter and have more weight. They're both great pickups.
I might suggest trying a Holydiver neck as well if you like the Thornbucker neck. I personally have not found very many BKP neck humbuckers that I like, because I find most of them a little too warm/dark/bassy (though not muffled). The Holydiver neck is completely the opposite of that though, it's very bright and jangly for a neck humbucker, it's a very interesting pickup.
My personal favorite of these is the True Grit, however. It's a more even EQ than the Holydiver and less hot, less compressed, but still tight. The True Grit neck is one of the better BKP neck humbuckers I've tried also, if a bit more of a "standard" sounding neck humbucker.
I found the voicing of the Nailbomb to be extremely aggressive, and not in a pleasant way. I didn't find it versatile at all, but it was good for aggressive, heavy stuff.
I hope that helps.
