It is an excellent tool for designing unregulated supplies and will give you LOTS of info. Very configurable for many types of designs (bridge, voltage doubler, etc) with different filter types (C, LC, etc).
It is meant for audio amplifier design so you will see some stuff that is meant for tube amps more so than lower voltage solid state stuff, so don't worry about that. A little math done on your own with the results will give you Pd in your voltage regulators and will let you make sure your unregulated supply isn't sagging below your dropout voltage at max load. It's good software.