@midogrumpy That's crazy helpful, thanks man!
The reason I ask about TSTAK is that when I do a search on homedepot.com, there are literally zero TSTAK SKUs in stock within a hundred miles of me. On Amazon, there are only a couple TSTAK products still listed and most of them are selling from third-party sellers at inflated prices, typical of the sort of thing that happens when a product is either discontinued or in short supply.
Lowe's still has Versastack SKUs available, but the 3-piece "system tower" kits are no longer available anywhere. This seems to align with the OP's observations back in December that Lowe's appears to be clearing these systems out.
I have a couple cordless tools that came w/ TSTAK boxes and I don't really need the extra durability or waterproof capabilities that come with Toughsystem. Versastack/TSTAK would be perfect but for some reason they're just hard to get in the US right now.