The Application Process

Hi,
I am an indian candidate,will complete 4 years of experience in August.I had applied for 4 colleges using my GRE score(1420) in Round 3. I applied to Kellogg,Cornell,Wisconsin,Olin(washington univ st louis). Kellogg rejected without interviewing me whereas i was interviewed by the rest.I had appeared for GMAT once and scored 620.
Finally i have received admit from Olin but was rejected by the remaining colleges.
Now,I am in a state of dilemma.Should i appear for GMAT,hope to score above 700 and then apply to better colleges or take up Olin?
My concern is that the top consulting companies do not recruit there.
Another reason for my dilemma is that after applying to these colleges,i won an international competition hosted by the economist and achieved other things that i havent put in my resume. Thus my inclination to apply for top ranked schools.Please throw some light on Olin as a school and its brand value.
Thanks for your time,
Shreeraj