I started mixing Max VG (85-90%) about 6 months ago. I was at 30-40% PG before that so I did a lot of trial and error in the beginning. When I first started mixing a couple years ago I found that I prefered all of my cream or custard recipes after at least a 3-4 week steep. I could
vape them before that but they really came alive after 3 weeks. I find the same thing with Max VG only they are less vapable at the 1-2 week point. I am getting pretty much the same level and complexity of flavor that I did before but now I have to wait at least 3 weeks until the flavor is at it's best. Simple fruit recipes are good to go after 3-4 days though.
Of course this is all just in my experience.