Troubles with Lockhart's Goon Grease

So I have really thick, wavy hair that basically afro's up if I don't style it. I've grown my hair our to about 3.5 inches and been going with a slicked back look. I recently bought a can of Goon Grease. I love the way the product holds my unruly hair in place, that it lasts forever, and the fact that I can restyle it hours later. The problem that I have is it's really hard to wash out and even when I do shampoo good, I feel like there's some residue left. Anyone have any suggestions for deal with this?

While I really like Goon Grease, I might be open to try different products if you guys have any suggestions for my hair type as well. I've used American Crew Fiber and Bed Head B Matte Wax before, but for shorter hairstyles. Do you think these products would work with my longer hair?