Spirocores are exceptional.
I have ordered these strings form my wife's double bass. We play together in quite a wide range of styles - jazz to blues to bluegrass to some light rockabilly and these fit great for all of the applications. Although arco is not what we ordered these for, they are great for that (also, it is very easy to clean resin off).
Slapping is possible, but will require some getting used to as these are obviously quite more rigid than, say, weedwhackers, however there are some famous slap-heavy players who use these.
Pizz is where these strings shine - deep, growly sound with lot of thwack but also a surprising amounts of the actual note. It, of course may differ, but I found that these really drive the bass - the sound is loud, resonant, you can almost feel the amounts of air moving.
Note that in the beginning spirocores may and will sound pretty bright - give it a month or two to get to their best.