In the same situation rn. Below are some of the info I gleaned (correct me if I’m wrong)
Army
•Biggest branch hence has the most specialty spots (but has to snowbird for a year after graduating DS)
•Locations are more diverse (but also means more undesirable locations)
•Fewer deployments, but usually longer if deployed (as of now)
•Can only military residency
•I read that BOLC has more actual “military” stuff? And that you will learn how to act as impromptu secondary commander
•Officers and enlisted mingle more
•Facilities are typically more dated
Navy
•Cares for both the Navy and the Marines(Upon your credentialing tour/AEGD/GPR(1-year orders) you will go to your operational tour(2-year orders). This is where you could be stationed in a carrier(multiple dentists), One-holer(smaller ship with one dentist), or Marines(overseas or in the US). For the ships you could either be assigned to one that is docked in port(for maintenance/repair/etc), one that is getting ready for deployment(6-8 months on average) or one that is in the middle of deployment(you will be flown-in to the ship). You could ask your detailer for a specific ship but that is not always guaranteed. As far as the marines you could be deployed to do small exercises(to overseas or other location to do non-dentistry stuff), hikes(4-6 miles with equipments). The exercises are normally short 1-3 months(marines rarely stay for long in the same area). Also, each year one of the marine battalion dentists will need to volunteer to go on the MEU(1-year orders). Basically you'll be going in and out of the ship but rarely stay afloat for more than 2-3 weeks. The most popular destinations for marine billets are in lejeune, 29 palms, and okinawa. What I mentioned above is the most likely scenario. But I have seen people get shore duty or do their operational tour starting their 3rd year but usually they have some sort of extenuating circumstances(medical condition, etc). Also this only applies to general dentists. Orthodontists, orofacial pain, endodontists, prosthodontists, public health, operative dentists, pediatric dentists don't go on ships but they(pros, perio) can still be assigned with the marines(although they won't be on the MEU). OS have one year orders on ships and comprehensive dentists for 2-years.