I've recently been able to print with dual extrusion for the first time thanks to the new Flashforge Creator Pro at my job. I discovered Makerware's purge wall feature and was wondering what others' experience has been like either printing with or without the purge walls. On one hand, I can see how it's useful in creating a nicer print. On the other hand, it does seem to waste a lot of time and material, plus it seemed like it made the actual printed object smaller than how it appeared it would print when viewed in Makerware.

Is it worth it to use purge walls? Are there settings that will still work but waste less time and material? Is there a good alternative to purge walls? Just curious what others think.