Yes, It doesn't matter what booze you use to 'feed' the cake. Brandy, whisky, Sherry - it's your choice. I even used a miniature of Buckfast Wine one year!
yes, you can feed it with anything to make it yummy and keep it moist. If preservation is your aim then the higher the alcohol content the better. Try drambuie or Glayva for yum factor, also cherry brandy
if it is christmas cake you are making, my best one was regularly moistened with Whisky. I dont even like Whisky but the cake was delicious and very moist. Topped it up once a week for about 6 weeks(did not even taste of whisky). sister used sherry and it was quite bitter