The Grand is taller but isn't really much wider. Here's a picture I took this morning with a mini to the right of the Grand in the center. I got used to the size of the mini first so it takes a little getting used to the grasp in the Grand. To do it over, I may have done it differently.
The mini will certainly get the job done for you. I don't see any difference in flavor. Battery life on an 18490 should last you most of the day but probably not all day if you have good
batteries so always carry a spare. I tend to leave for work with three
mods and have a battery charger in my office. I do that more for flavor change though.
You can't go wrong with either.
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