When choosing a "heavy oil" ball, you have to consider a few things: Is this oil condition "heavy oil" or "a flood!!" How long is the oil pattern? How clean are the backends?
If you are on a true absolute flood, particle is your friend. Otherwise, you can probably use a strong reactive that will eventually help burn up a friction spot.
The next question is what kind of reaction do you need? Are you looking for a rolly, controllable ball, or are you looking for something that has a little more backend snap? For example, you might use a Dimension when the backends are spotty and slick and you need to rely more on the midlane to get the ball to face up to the pocket. If you have a shot that gives you a little more room on the back part of the alne to bring it back, the Virtual Gravity will give you a stronger, more angular backend reaction while still picking up quite a bit in the midlane.
And, as always, remember to square up some and stay behind the ball to create earlier roll and a better ball roll when facing heavier oil conditions.
