Yes! You do! You just don't know it yet! Mine sat in the box after receiving it from my Dad for Christmas as the stuff I was working on didn't have hardened grease. Just sticky/waxy so cleaned it all by hand. Was in a bit of a rush on a project so tried it out and am hooked on using it for as much as I can. Most stuff, if not completely hard comes off in 10-15 minutes. Saves wear & tear on my aging hands as well.
The one my Dad gave me came from Amazon. 1.5 litre I believe. Big enough for a chain or both hub guts & bottom bracket(be careful with copper & Simple Green solution) The chain above was encased in hardened automotive grease from an early 60's German lightweight.
EDIT: Mine is also heated. I typically set it at 40°C.