Sorry for the late reply, for I've been away from the forum for a while. Since no one seems to have answered your question, I do feel that there is a subtle, but distinct difference in tone between the Pinnacle and the ABR-1. If I'm not mistaken, I think that the base on the Pinnacle is indeed aluminum, and I'm not sure about the saddles. The ABR-1 is definitely zinc with brass saddles. To my ears, the Pinnacle sounds a bit more "airy" and a bit scooped while the ABR-1 seems to have a little more of a direct punch in the mid-range. The attack on the ABR-1 just seems to be a little more immediate with a little bark thrown in, if that makes sense. I mostly prefer the ABR-1 primarily because it has more of a traditional vibe going on, both in tone as well as aesthetics. It's also a tad narrower than the Pinnacle, so it typically does provide a tiny bit more clearance between the strings and the bridge. It's pretty marginal, though.
Heritage started using the ABR-1 style of bridges with their 2025 CC models, and I believe they're made by Advanced Plating. They're practically identical to what Gibson has been using for their CS Historic models for many years with the exception that the mounting holes are drilled larger to accommodate the 8-32 thread pitch on a Heritage bridge post vs Gibson's 6-32 thread pitch. If one so desires, the Heritage bridge is a direct drop-in replacement for the Pinnacle bridge, so there's no need to swap out any bridge posts or tailpiece parts to install one. Unlike the Pinnacle system, the ABR-1 is not locking, so that may be a deal breaker for some folks. However, Faber does offer a Tone-Lock bridge that can be directly installed on the existing Heritage posts while using the Pinnacle thumbwheels, but the thumbwheels will need to be turned upside-down in order to have a flat surface for the bridge. It's also necessary to use the Pinnacle tightening screws to lock the Faber bridge in place, but it does work.
Interestingly, Heritage clearly dumped the Pinnacle bridge on their CC models in 2025 in favor of the more traditional ABR-1, but I've never heard the reason for doing so. If one is concerned about saddles falling out when breaking strings with the ABR-1, it can be an issue. I also know that the Heritage ABR-1 bridge, thumbwheels and bridge posts can be purchased through Mike at Heritage, so they are readily available to anyone looking for that kind of a setup.