Note: those who don't want a long lasting effect but a strong short term effect consider vaping over rectally.
There are many brands of vape pens out there and depending on the fluence that someone wants, the speed of the atomizer will determine if the micron size is large or small. The fastest speed atomizers will make the cluster size of the vape juice nearly bone dry. Some of the vape pens people use for CBD have a larger cluster size and have a more full, dense feeling. This may seem appropriate but just like those buying essential oils, some people want a lower micron size vapor that fills up the entire room and some want a heavier, larger cluster size vapor that doesn't travel as far and only fills up a small area of the room. The heavier the cluster size the heavier the vapor and the smaller the micron size the easier.
Note: for those that really want a high end vaporizer, some of the non portable vaporizers that are used indoors are preferred. I prefer to have the cluster size of my cannabidiol the smallest micron size.
Note: vaping has a quicker effect but doesn't last as long. CBD taking orally lasts longer in the body but is absorbed slower in the body.