@streakmachine I started my collection of Ryobi battery tools about 16 years ago with a hammer-drill using 2 NiCad batteries. Later I bought a wet & dry vacuum & a twin-tube fluorescent lamp. When those batteries died I discovered the One + batteries were compatible so I bought a 1.3 Ah lithium battery & charger to see if it would work.
Since then I've bough more batteries, some genuine & some cheapies from Amazon, I have three 2.5 Ah & a 5 Ah. Other tools are a multi-tool, 12-in bar chainsaw, tyre pump/air bed inflator, line trimmer with nylon cutting blades & last summer I was contemplating getting a misting fan.