I'll sum up balanced armature vs dynamic driver
Does not cover wide frequency
Small in size and capable of having many drivers with crossovers
Detailed and analytical sound
Does not need a vent, so better isolation
Generally more pricy
More sensitive than dynamic
One can cover the entire frequency
Rather big, but they are capable of having upto 3 drivers in a iem as of now
Warm detailed sound with good bass rumble and impact
Harder to drive than BA.
Usually needs an vent, so less isolation
Usually has one dynamic driver for bass region and multiple BAs for mid/highs.
Well regarded for spectacular bass while keeping other frequency clear.
Things can go wrong as BA and dynamic sound different and some people can notice the crossovers changing
Generally have a vent, and bit heavier than BA customs.