I would not recommend the Skid for heavy oil, for that depending on just how heavy,in the Roto Grip HP4 line I would look at either the Hyper Cell solid or the new Menace. The skid is an awesome ball, but not for heavy oil, due to the pearl cover, it will "skid" too far before the break point. That's what the H/C solid is for - BUT, if there is not enough head oil - it will burn up. The Menace is supposed to fit under the H/C solid to use when that ball is just too strong to use. I am also looking at the Haywire to compliment my H/C solid. So after they come out and I can actually see what they both do,then I will make my decision of which one of these to get, but I am leaning towards the Haywire. I don't know about the Tag for light. I use the Uproar.