I mostly don't have the patience for steeping; it's really only worth it to me if it's a choice between letting it sit a while, or throwing it out -- I'm kind of a pack rat, so I'll let some bad ones sit for a while before I finally throw them out. I've only ever run into one that needed the airing-out, a Virginia that I purchased from somewhere, was really strongly chemically-tasting; I let it sit undisturbed with the cap off for about a month, and it helped.
Now that I'm doing more DIY, I may let some juices sit for a while if they're not great right after I mix them. Still waiting on a couple to see if they improve or if I need to find a different recipe or what. But in general I prefer not steeping -- I may or may not ever taste those ones that sit for a while; if it's not good right off the bat, I'm on to something else, or back to whatever I'm currently vaping.
Andria