I need some clarification on chargers.  But first, my Mini is arriving today around 1:30.  Yes!  I can't wait!  This will be my first Provari.
I have an UltraFire rapid charger for 3.7 Lithium 
batteries.  Is that okay?  I don't yet have a Pila charger.  I have several AW IMR 18350 
batteries to use with my Mini.  I've read here that the batts should come off the charger at 4.2V.  How do I check that using the Mini?  And just in general, is my charger okay or should I 
buy a Pila charger?
P.S.  Do we have to sign for the package or will the postman just put it in the mailbox?