Interbase vs MS SQL Server ?????

We are looking at an SQL Server for use with initially approx 35 clients
with the ability to easily scale up.  The front end will probably be
written in Delphi.

Can anybody give me an opinion and reason as to which SQL server they have
chosen or would choose. So far the main competitors have been narrowed to
MS SQL Server and Borlands Interbase Server.

Also, if any one could point me in the direction of other independent
reviews or comments.

Thanks in advance.

C Fraser