I love Arizer and have reliably used the same ones daily for years. The Air is slightly smaller and has replaceable 26650 batteries whereas a Solo II has an internal rechargeable battery and is slightly bigger. Both are portable but probably a little clunky to carry around in a pocket. They probably will be on sale shortly with 4/20 approaching.

Edit: dry herb vapes make your herb stash stretch an incredibly long time versus combustion because it uses so little.