Yeah, i did the math like this:
1 year internship
2 years GMO (at the conclusion, will have 5 years to pay back)
2 year medicine residency
3 year utilization tour (at the conclusion, will have have 2 year to pay back)
2 year cardiology fellowship (say in military)
3 year card utilization tour (at conclusion, payback finished)
--------
= 13 years
+ 7 years (active duty prior service)
--------
= 20 years
+ 4 years at USUHS
---------
= 24 years total service. (i think this agrees with your assessment, i just added the usuhs years last)
As far as money goes . . . I made a spreadsheet, comparing civi and milmed tracks for me. Of course some assumptions went into it (i.e. for a Civi card i used an average salary of $300K, private med school etc) . . .Over the time period described above, I calculated that a civi card would come out on top (med school loans and all), by about +$600K.
Now, I could join my civi card counterpart at age 50, and have about a $125K retirment (using a calc. that takes into account a 3-4% pay increase every year, assuming retiring as an O-6, etc). So I could erase that 600K delta in about 6-7 years. Then enjoy that retirement for the rest of my life!
Anyway, the numbers work out for me, albeit there's a lot of assumptions. I encourage everyone to do an analysis like this.
But again . . . .I also want to serve . . . that's the most important thing.