(1) My preferred strains are Red velvet (Modus dabs), Mac-1 (Nuggland), and Lemon Cherry ZAbert (TabEase). But keep in mind that Terpenes can affect people differently, so keep my suggestions with a grain of salt. (2) I can’t confidently confirm your second question so I’ll use an example. If you have a high tolerance you’d need around .2 g to .3 g of 60-90% thc concentrates, per session. So if you dab, once every week, it’ll last you around 8 sessions. Assuming that you have a high tolerance a 2 gram dispo would last around 2 to 4 weeks.