Von, from what I see myself as a silver subscriber here are limits:
SILVER
Armor: Can wear anything but legendary and fabled items (we CAN wear mastercrafted items)
Weapons: Can equip anything but legendary and fabled items (we CAN equip mastercrafted items...although for some reason I was not able to equip a mastercrafted quiver...a little strange, but I thought I would mention it)
Crafted spells/skills: we can upgrade spells to the Expert tier level (I believe this is what the mastercrafted skills/spells are)