Steam distillation on pseudo from what SWIM has read is not all that great. SWIM has only tried it once in the past (about a year ago) on some red hots that were much simpler and cleaner then. SWIM spent a long time distilling, and collected a bunch of distillate, but very little pseudo was extracted from it. The still flask contents had started to burn during the course of the distillation, turning the gups and water dark blown and eventually almost black. This was dumped into a beaker after the attempted distillation, and acidified until the pH was very low. It was filtered free of any insoluable gups, and re-basified until freebase smell was detected (and it smelled like my yeild even though it had been partially distilled). The solution was covered an placed into the freezer for an hour, then the brownish dirty/scorched freebase flakes were filtered out. The filter was allowed to sit for 30 minutes or so to dry out some and the filter cake was scraped out. It was dissolved into hot methanol, filtered, acidified with HCl acid, and evaporated. The pseudo that resulted was still in good shape, although it had turned a slight brownish color after all that. It was ran through an rxn (short p/p back in those days) and yeilded superb product.
Nowadays, SWIM suggests to try some of the current pill cleaning methods before attempting to steam distill. Follow the info on the thread for 120's (the new procedure thread). Extract with alc, concentrate, add KOH and some H2O and boil for a few to destroy polymers. Filter, and extract with non-polar. Heat non-polar extractions until all alcohol is driven off, then filter until clear. Gas or titrate to receive the goods. Of course, recrystallize it. Then run a small amt of it in a nano and see what the outcome is. If it's alright, do the rest. If there are gaks still present and the post rxn a/b seems to be gakked and the product comes out dirtier than usual, then steam distill. SWIM found it is better to clean the pseudo as best as you can without distilling, then run with a little extra I2 and rp to help overpower anything else, and then distill. If you do it right, all the pseudo will still get reduced in high yeilds, and the distillation will purify it to a much higher quality (as if it were distilled [the pseudo] pre-rxn. SWIM just found that meth freebase distills over with steam quite readily, and is much easier/quicker to distill. Although the drawback is it'll cost more I2 and rp in the long rung cause you have to add extra to help overpower any remaining gaks should you have problems with the pseudo.