On the matter of crock pots and slow cookers, that's a redundant piece of equipment. This list already includes a dutch oven, which you can use for the same purpose. The other piece of equipment which you already have is an oven. As long as you've done the work to calibrate your oven (get an oven thermometer), you have what you need.

What temperature is a 5 on the slow cooker? Who knows? 200 F is pretty easy to understand.