When you want a tool that can merge video files of different formats, then All Video Joiner can come to your aid.

This tool recognizes AVI, MPG, FLV and DAT extensions, and can output files to the AVI, MP4, MPEG, VCD, SVCD and DVD format.

The interface of the program is standard and easy to navigate through. You can add files to the list by using the "drag and drop" function or the classic file browser.

In the list you can view the video size, start time, end time and subtitle file of each source file, but you can also preview videos in a small window, as well as sort files. Once you have selected an output directory and format, you can initiate the merging process.

In the "Options" menu, you can configure general settings (e.g. keep original duration, select aspect ratio, zoom video), as well as options for each format type (e.g. video frame rate and size, audio bitrate, channels and sample frequency rate, bits per sample). Resetting settings to default is also possible.

All Video Joiner consumes a moderate amount of system resources, has a well-drawn user manual with snapshots, finishes a task in a reasonable amount of time and keeps a good image and sound quality in the output files. Besides its merging function, it can also be used as a video converter.

Unfortunately, the shareware version has its limitations. Otherwise, All Video Joiner can be used with confidence by both rookies and experienced individuals.