...needless to say that if you have a boom mike you save a hand - so the safest way of communication by far.
That may be open to debate, in a two crew cockpit, the PM/PNF or whatever your terminology may be still needs to use one hand to push the PTT button. Your comment might be appropriate for a single pilot airplane being handflown with a PTT on the yoke.
On another note regarding the comments from cough and downsouth, some companies really make an effort to SOP anything
But this is off-thread. Rainbird, I donīt think the use of an intercom/headset is really going to make or break your career, other ways might be more feasible. Most pilots do not like having "clamps" on their heads for long-haul, nor listening to the other guy whistling, coughing, sneezing and you name it through the hot-mike. At least I did not like it much during my turbo-prop years.