unless the thing returns is drilled very weak, i dont see you being able to use it on light oil due to the fact that the rg is pretty low and the coverstock strong, even though its a pearl. if it is as weak as you say though, and you would like to try a particle pearl, i would say pick up an eraser particle pearl and drill it 4 x 4.5. this should give it more length then the diesel, and should really let you see what a particle pearl is capable of. the eraser is one of the most popular balls in my area, even though it is older, and i have liked the reaction i've seen with others throwing the ball.
i have only thrown one particle pearl, a rock star, and was very impressed with it until the lane machine ate it. i ended up getting a command zone arc which was one of the best balls i have ever had. i see particle pearls as being similar to solid reactive balls, but that is just my opinion. as for a solid reactive choice, i would go with an original inferno. very solid ball, and if it is a little weak, you can always dull the surface a little.
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stanski