grosbouff, so you have a set of administrative default filter settings, and you’re going to let users set their own filters and customize existing queries? Is that right?
If so, then Andy is of course correct. It won’t need this in a session because once the plugin is loaded via buddypress, the info is available without any additional queries to the db once the data is acquired for the first time. It shouldn’t slow anything down, other than the initial gathering of the data.