MailsDaddy PST Merge and Join tool is a flawless application. With this utility, you can easily merge several small PST files into a single PST. This economical solution provides two options, first join PST file and second merge PST. With the Merge PST option, you can skip duplicate emails and create a new PST file for all PSTs.
The best part of the solution is that it keeps data content with relevant emails. So, you don't have to worry about contacts, calendar, task etc.