As long as your university is adequate, education is what you make of it. You can go to Yale, not learn very much, and not go very far in life. Also, you can go to Yale, not learn very much, and become president. (So maybe we should be trying to become oil-millionaires, instead of physicians). I went to an "average quality" state school, got a great deal out of it, got into my first choice graduate program (top 10 in my area of specialization), and into my first choice medical school (24th or something nationally, according to US NEWS) on my first attempt. I am where I wanted to be, and it didn't cost me much in tuition.
If you are a really bright and motivated student, and you don't want to be president or teach at Harvard, then you probably don't "need" a "top" school to achieve your goals.
I tend to believe that it is the unimaginative, & unmotivated who benefit most from being at a "top" institution. However, if you are clever and a pleasant enough person, your teachers will recognize this, your grades will be good, and you can benefit from their attention, guidance, and connections. This will be true of both "top" and "non-top" private and public schools. If you are not much of a self-starter, look forward to outrageous grade inflation, or have impoverished people skills, going to a school with a "top" repuation may add something to your chances, so avoid public education. Alternatively, if you plan a carreer in national politics or you need to network exclusively with people of sufficiently high breeding, then going to a "top" school is probably also a good idea. I had a friend who went private so she could be around people who were in the same socioeconomic class she was, and who would recognize who her family was. These are also good (though perhaps shallow) reasons to go "top" over "non-top" or private over public.
I discovered that I could build a fantastic resume and strong connections through being an excellent student at my state university. This is also a great way to develp resources and connections in the local business and political scenes. I went to a large, public, urban research university, and found wonderful teachers, great mentoring, and lots of opportunities opened up to me through these faculty relationships. Good students can come from most anywhere and go most anyplace they want. Some political/class issues are also a factor, so depending on your career goals, a top undergrad school may be a better choice for you. (Top private schools tend to hire more faculty from other "top" private schools, and a few "top" public schools. When people make babies in this way, we call it inbreeding. When you hire faculty this way, it is called building prestige.)
I was raised in private schools, and was unable to imagine myself at a public college. Nonetheless, one thing led to another & I ended up at a local public institution. I am thankful that I was able to swallow my pride and take full advantage of the many opportunities that came my way at my "average" public school. Today, I am an enthusiastic supporter of my alma mater. Because of this experience, I have fairly strong feelings about discussions like these. If I ever have children, they will probably attend private schools through 12th grade (unless we move into one of the better school districts in town), and I hope that I would support my child's matriculation to either a public or a private college--whether it is a "top" school or a "non-top" school--as long as his or her reasons for choosing it were appropriate.