Doing some searching on eBay, it turns out Maisto's (Adventure Wheels) Slickers have been around longer than I thought.
Searching 'slickers' in the Diecast & Toy Vehicles section came up with 9 results. 5 Maisto Slickers 8-packs under the 'Fresh Metal' line (likely from the '00s), 2 Tonka trucks, and 2 individual Slickers, on card, from 1992.
So, it seems, that their Slickers are at least as old as I am. Who would've thought, right?
But I wanna focus on those two from 1992.
The first one has an '80s Pontiac Firebird look to it, complete with T-Tops.
The other one has a Porsche look to it. There's a 935 on the front end, but it looks more like a regular 911 than a 935. :/
Figured I'd throw these up here, in case Frosted or anyone else is interested in some older Choro-Q/Penny Racer-like Maistos. :D
Oh, and here's the rest of the '92 Slickers lineup, in case you guys are curious.