I don't use my slow cooker much anymore, but I think a lot of people who do use one are looking for convenience and a minimum of messing with and attending. And even though that's not often an issue with me, I still appreciate being able to brown over high heat in my Dutch oven and move it to the oven to cook. And that's the selling point here, with the pot being designed to stand high burner heat and then move to the cooker. It's not really "one-pot" cooking if you have to brown in a separate pan first. So this is genuinely one pot.
As to "slow cooking," it is my opinion that any slow cooker must have at least one cooking setting somewhat below 212F (100C). Typical slow cookers do not have thermostats. They are designed aimed at the heating element staying at a preset temperature for each setting. They don't pile on extra heat to get started, which is why a cold start calls for pre-heated liquid. Over time, the temperature in the pot will equalize to the element temperature.
But I do find that most will boil on the high position, and I would prefer some things not to boil for esthetic reasons. So, what you want to know is if the Low setting is around 175F (79C) or a little less, which will cook in reasonable time without boiling. I mean, if I want to boil, I don't need a slow cooker, because any pot will limit out at the boiling point, even on a high burner. You will see that slow cooker makers never associate particular temperatures with settings. They're not intended to hold precise temperatures.
Now, there's slow cooking and SLOW cooking. A slow cooker is not for sous vide. It hasn't the range nor precision. It's for cooking slowly with little risk of overcooking, and it's pretty strictly for braise type operations where well done is the expected outcome. Remember the difference. Doneness means temperature, and slow cookers are always above the well done range. Tenderness means time, and it's what slow cookers do well.
As to servings, it says 4.7L. Figure probably 4L practically, so eight servings, if everyone gets about two cups. Sounds reasonable for hearty meals.