I'm really not too sure about the nausea thing - I mean, I definitely boiled and then dried out and crushed the seeds up pretty much every time I've done 'em. Like I said, only saw one person get sick - BUT - I think that if you were to just get like, Burpee seeds or something, there would be more crap on them. There are places online where you can get more "untreated" seeds which is what I did, and the other friends who've purchased seeds did.
Apparently, nausea can still be a side effect of 'em, even if precautions are taken...but, then again, it's like that with shrooms, too. I've seen people lose their lunch after taking shrooms.
BUT with that said, I would recommend 'em as a substitute. The trip isn't as long by a long shot, and it's not as strong as illegal psychedelics, but if you test yourself on a light dose as per this
handy dandy table, you can see how you're affected for future endeavors.