I have tried FPDF and chnaged to TCPDF because of lack of funtionality available in FPDF. I suggest to use TCPDF because it is much more powerful of FPDF, Well structured class and less buggy.
Some of the powerful features of TCPDF that are not included on FPDF are:
•Source code full documented.
•PHP5 class and PHP4 alternative.
•support for UTF-8 Unicode and Right-To-Left languages (including a bidirectional algorithm).
•includes support for backward editing (edit a previous page).
•support for document encryption;
•methods to publish some (x)HTML code including complex tables;
•a large number of graphic (geometric) and transformation functions;
•PDF bookmarks;
•Javascript and forms support (you can also save the forms content);
•supports user rights management so Adobe Reader users can save filled-in copies of forms they complete.
•method to render various barcode formats directly on PDF.
•support for TrueTypeUnicode, OpenTypeUnicode, TrueType, OpenType, Type1 and CID-0 fonts.
•supports custom page formats, margins and units of measure.
•includes methods for page header and footer that could be easily overwritten.
•supports page groups.
•supports clipping masks and stroke and clipping mode for text.
•supports CMYK, Spot Colors and transparency (in addition to Grayscale and RGB modes).
•supports links and annotations.
I didn't tried all features but created well formatted invoice with images.
Following is one of the sample report that i have created using TCPDF class.

- milkbill.png (65.77 KiB) Viewed 5277 times