This may be true when you leave at 27 and 5 yrs in, but it will have little or nothing to do as the reason when you leave at 8, 12 or 20. You will be treated just like every other job candidate. Your RESUME regarding your job positions will be your make or break. Companies do not care at that age where your undergrad came from, they want to see your job progression and if you fill the squares for the position. They are not going to take the SA grad who did not get a Masters over the ROTC grad who did. It does not make business sense. The airlines are not going to hire the SA grad who flew A-10's over the ROTC grad who flew F-22s just because he is an SA grad. Defense companies are not going to hire the SA grad who never did a Pentagon rotation for a Pentagon job over the person that did.
It is what you do after you graduate that will determine how your corporate career chances will pan out.
If you are starting to weigh the option o only doing a 5 and dive, I would suggest that you be smart, and as soon as you get to your 1st base, get your Masters on the military dime. You should be able to complete it in time so you owe no more time back. That way you are still close enough for your undergrad degree to matter, but you give yourself a leg up with a grad degree.
Think about it, let's say you leave at 30, are you trying to get an entry level position in management? Of course not! Thus, you will admit that your career positions over the last 8 yrs and a Masters will be of more value than who your commissioning source is.
I would say, that the SA from an academic point does give a better advantage than ROTC for one reason. SA cadets have a higher chance to get great academic slots after graduation...Harvard, Rand, Rhodes, etc. That will translate into a major plus not only for your military career, but post military, regardless of when you leave. For example, every yr the SA will have cadets that go directly to Oxford, Harvard, MIT, Rand, etc for their Ph.D. They will incur an additional commitment, but it doesn't matter. The military has tagged them as their future leader, thus their career will be given an early edge. If they decide to leave, what company is not going to say take the guy with a Ph.D from MIT? That being stated, just because you are at an SA does not mean you are competitive for these scholarships, you will need to be the best of the best to even get the chance to compete for this, and when you do, you are competing against not only other SA cadets, but students from around the country.