I have 2 30ml bottles of complete yuck from MB that wouldn't get better if you steeped them for a year.
I'm really starting to think the entire concept of steeping is just something made up by vendors who don't want to take the time to mix their juices before they sell them to you. Both PG and VG are pretty thick substances and are very different from each other, so shaking them up doesn't really mix them well. I've been experimenting with DIY and what I found it this. Put it in a beaker and use a glass rod to stir it. If you don't have a beaker or a glass rod use whatever just as long as it's clean (pg has anti-bacterial properties so there's not much to worry about as long as what you use is clean). If your juice isn't "steeped" pour it into a small open faced container and get a spoon or whatever and simply stir it vigorously for about ten minutes. Then put it back in the bottle. If it doesn't taste good after doing that there isn't anything that "steeping" it is going to do for it. That's myanyway. The only reason I can think to leave the lit off and let it sit for a while is to let alcohol or water evaporate. But mixing is mixing, so if it needs to be mixed, unlike James Bond, better stirred than shaken.
Geeez, well yet again you are incorrect! Why bother replying when all you seem to want to do is to slam MBV, and yes most require aging and do mature and aging freshly made juices does improve the flavor immensely.