The last LSP I put on my Kia Spectra about a month ago, was Collinite #845. And then just yesterday applied a coat of WGDGPS 3.0. I've done this more than once, and would like to comment some on some of the differences I notice:
Collinite #845 is a great product, very easy to use, a bottle goes quite far, and the protection it gives is very good. And another great attribute, is it's reasonably priced.
But with WGDGPS 3.0, and what I quite quickly recognize, is that I see much greater clarity of paint, especially on dark colors, which my Kia's Magenta Pearl-Metallic paint is fairly dark.
I might then conclude that WGDGPS 3.0 might have more in the way of paint cleansers added, that will better remove any films and caca from the paint as you apply it. Not much mind you, but enough that there is a difference in look, and I have to give the Wolfgang product the win in this comparison and quality.
That most likely on your black paint, things just might look a whole lot "blacker" with WGDGPS 3.0.
While Collinite #845 might have more in the way of a petroleum carrier, and might be effective at removing grease or oils, I don't really think its abilities go much further than this for "cleansing" paint. Now if the vehicle's paint has just been previously cleaned by either polishing or a paint prep scrubber-cleaner, then one might achieve better results with Collinite #845 in this regard.
And to me, the Collinite has a slightly "warmer" look than WGDGPS 3.0, which the latter is no doubt a pure synthetic paint sealant.
I note much sharper, dazzling reflections with Wolfgang Sealant, the paint appears much more vibrant, and the gloss is more "glassy and dripping wet" looking versus Collinite.
I see no advantage using either as a follow-up topper immediately, just extra work, and probably a waste of either product. That to let each product live on its own for a bit, and then like I have recently done, no harm or foul to switch back and forth between the two.