I don't know anything about your playing level, so forgive me if I write things that you already know. Each player is different, each rally is different, each shot combination is different but I believe some helpful tips are:
- You need to understand how pimpled rubbers work and to be very focused cause spin variation and placement are the choppers' weapons. It's the combination of your previous stroke and the chopper's stroke that determine the spin of the ball you receive. For instance, a pimple-chop after topspin will lead to a back-spinning ball. The heavier the topspin you play, the heavier the backspin you will receive. On the other hand, if you play a backspin ball and the chopper pushes it with the pimples you will most likely receive a no-spin ball.
- Try to hit the ball on top of its bounce when the spin is minimum, thus your shot will be easier. For that, you need very good footwork in order to be in place.
- Although you find it hard,...be patient.
- mr. tom's advice is also right. I especially find very effective to vary deeper with shorter topspins.
- If you still find it very hard to play a chopper, try to avoid his pimples and try to be agressive early at the point before the chopper gets into position and rythm.
- Have a strategy and don't just let the chooper get you to play his own game.
I hope those help...