Of course, all plants have a odor.Colonizing jars can be pretty strong, sometimes they will develope a strong sour odor before the mycilla takes over. After that it just has nice mushroomy smell.
If you keep them covered and have halfway decent ventilation no one will be likely to notice it, even if you have jars that spoil badly. If you keep them in a small area though, they can stink a bit when you take them out, but usually not for long.
Jars don't always smell bad, it depends on the substrate. I've noticed that they seem to be prone to getting sour if you use high water content.
Once you have them birthed they should not smell like anything other than mushrooms.
I love the smell of a nice grow chamber.
[This message has been edited by Code (edited January 30, 2000).]