I don't think you can get anything like a definitive answer to this since plywood is now so notorious for how much it varies within a given class. As a result, even if you managed to find an existing head-to-head comparison that looked thorough (best of luck with that!) it may not tell you anything that is actually directly applicable to your situation.
If what you're doing is really critical probably the best advice is to run some tests of your own, assuming you have the time.
If you don't have the lead time then "you pays your money and you takes your chance" as the saying goes. But FWIW consider that concrete-form plywood, although expected to withstand getting wet regularly, is not actually made for continuous exposure to the elements.
For what it's worth, assuming you buy a reliable brand I doubt you'll be disappointed in the performance of the marine-grade if treated right; this seems like it's right in its wheelhouse :-)
With edges sealed well with CPES (probably the best sealant option, assuming no UV exposure) I think you're likely to get the best long-term durability. If any edges are exposed to UV they should be further coated with something to protect the epoxy.
Note that upkeep will be necessary if a long service life is your intention, this means regular refreshing or renewal of the chosen topcoat (possibly annual in the case of transparent finishes).