Playing against a player who uses long pips can be incredibly frustrating, or it can be really quite simple.
You must first understand the effect of long pips. Regular, inverted table tennis rubber sends the ball back reversing its spin upon impact. A regular rally consists mostly of topspin balls.
A topspin ball reaches the top sheet, grips the rubber and deflects it in the direction of the spin. Once the tension on the top sheet reaches the maximum, it snaps back like a rubber band and imparts the opposite spin on the ping pong ball.
Long pips bend under the pressure of the spin and don't offer enough resistance to stop or even invert the spin. The ball maintains its spin, but travels in the opposite direction. Topspin now has become underspin and vice versa.
Understanding that simple fact makes playing against long pips predictable. If you loop a top spinning ball and it is blocked back with long pips, you must expect an extremely heavy underspin ball.
Conversely, if you drive an under spin ball into long pips, you will get a slightly top spinny ball back. The spin is absolutely foreseeable. Once you've mastered that, you'll be looking to place the ball wherever the long pips are because you know exactly what to expect.