What are some pros and cons of doing ROTC while getting your masters degree instead of doing it as an undergraduate?

If you do ROTC as a Master's student, you will commission upon completion of the Military Science classes regardless of where you are in completing your graduate program. So you are on a 20-month timeline to get your degree because that is how long it takes to get through the MSIII and MSIV years. I know most graduate programs are 2 years but when you add ROTC requirements into that, it may change. Regardless of what component you enter, you will go to BOLC after commissioning so if you do have your degree complete then, you may have to postpone completion. As for undergraduate, you need a Bachelor's degree to commission so you need to finish that degree.

As an officer, if you really want to get ahead, you are going to need a masters so if you can get it while in rotc you are that much more ahead of your peers. There really aren’t any cons.

In my opinion, getting a Master's degree is hard enough without adding ROTC. But it is possible if your willing to work at it. You just may not have much personal time at least till you get "settled down". It will just depend on you. I had been unemployed at the time when i got my Master's but I do believe it is possible. There are always athletes in the top of their field getting 4.0's in the classes and i have seen some working on Grad school during part of their school year. If they can do it then anything is possible if you work at it.