Vantaggi
As a Junior Officer I was paid just under 100K a year until I hit 0-3. Healthcare is covered. Countless other military benefits. The people around you are genuinely not trying to undermine you and there is a good cause of defending the nation that motivates everyone.
Svantaggi
As an Officer, I was a glorified pencil pusher. I had little ability to contribute to the mission, other than sending emails and writing reports. I personally would rather get paid 65K a year to do meaningful work than 100K being a cog in the machine, not being useful for 10 more years. Also the military can't reward competent people well: Someone who busts their butt 60 hours a week gets paid the same as someone who takes frequent smoke breaks and medical appointments.