Find a familiar stable disc - Roc would be a good one - get a variety of weights, throw 'em, and see how they fly for you. You could try DX Rocs at 175, 165, and 155 grams, and this experiment would cost around $24.
If your form is reasonably clean you should find that lighter discs fly about the same as heavier ones, but farther. Stable discs are fly stable, wind or no wind. Wind does blow the disc around more (air bumps, that sort of thing).
For much more detailed information, see:viewtopic.php?f=5&t=12061&hilit=150+lovers
If you run the experiment, please do post your results.