MS Office Student/Teacher 2007 over MS Office Professional 2007

My sister is thinking about getting a new Toshiba laptop that comes with Microsoft Office Professional 2007 90 day Free Trial. She already has a CD of Microsoft Office Student and Teacher 2007 which she would like to use with the new computer. Will this present a problem or issues installing MS Office Student and Teacher 2007 over the MS Office Professional 2007 90 day Free Trail which comes with the new system?