Open-source software packages have various functions. An important factor is choosing the right package. On the other hand, no organization is responsible for these packages. In this regard, using the users' experience can be a good option or method in selecting the right package. There are many online forums which users discuss their experiences about the open-source software packages. Analyzing the data from these forums can help users to select the appropriate packages. This paper evaluates three top open-source software packages, namely QGIS, GRASS, and Gvsig, based on online forums covering spatial issues. In addition, the paper compares software packages and forums based on users' behaviors through a new approach, namely a Recency-Frequency-Satisfaction (RFS) method based on Recency-Frequency-Monetary (RFM) in Customer relationship management (CRM). Finally, the paper analyzes the procedure for using software packages by users’ comments by year. The results show that QGIS was used more than the other two and that the procedure was in ascending order for years.