good - dont worry about cash, and where is the nearest ATM...
bad - you must maintain control in order to avoid surprises and red numbers in your account.

to avoid interest, I always pay the full balance of my credit cards at the end of the month.
It is nice to have "like a little loan" from the bank so you dont have to touch your money from the bank and it generates interest for you.

War looking for peace,
is like fornication looking for virginity.