FastReport Open Source has just appeared, but I can already anticipate some of the questions users. Due to the fact that the export of the report in fact possible only in HTML format to many of you attraction of FastReport Open Source may seem questionable. And you may wonder, "Is it worth starting a project on open source version of FastReport Core or still fork over paid version?". I can tell you this worth it. Firstly, the Open Source has a great advantage - open source code, which you can modify as you wish. You can write your own export or use someone else's operating experience. Secondly, FastReport Open Source - it's the same as FastReport Core, just a little cut. Hence, they are compatible. You can start your project on an open source version, and In case of necessity of advanced exports - migrate to the paid version. It is easy enough to do this. You just need to replace the libraries of FastReport.OpenSource and FastReport.OpenSource.Web onto FastReport and FastReport.Web.
Migration from FastReport Core to FastReport Open Source is also possible, but you will have to remove all report exports from the application code. Besides exporting to HTML, of course. Web reports would not work without it.
The advantages of FastReport Open Source are free and open source code, and to the advantages of paid are rich functionality and technical support. I must admit Fast Reports devotes a lot of time to the development of exports, they really work well and have a lot of settings. Not so much reporting tools can offer such advanced settings export to PDF. Using the open source version, you should understand what kind of exports you are losing:
However, ultimately, it's only your choice. If you want to experiment and test your might, you should better start with the FastReport.OpenSource, if you need a reliable ready-made solution with full functionality and support, FastReport Core, FastReport .NET to be precise, which is composed of the components in the framework of .NET core is definitely for you.