I can't tell you about those specific brands or components. Both of the bikes (Ross and Schwinn) look comparable as far being able to upgrade if you need to. Both look to be from a time period when both were considered good brands.
Your price range limits whats available in a roadbike (at least the newer ones). I probably wouldn't hesitate to get either of those bikes. In your case you have to factor in what is available in your area at this time of year.
Since the guy selling the bikes seems knowledgeable ask him about upgrading. Judging by the bikes he seems to know quality from junk. He might be an old mechanic who could tell you a lot about bikes from that time period, but doesn't keep up with the new stuff.