With the exception of the Grade 5 FSD, you can get away with well-rolled Grade 3 for everything else and get results that are nearly as good for far less effort invested. Occasionally, a Grade 5 is enough to tempt me to farm materials for though, like Grade 5 Overcharged multicannons for example; They have no jitter, whilst Grades 1-4 add jitter which makes them far less useful.
Farm materials for something if you can see a meaningful difference between G3 and G5, otherwise you're likely to get several good G3 rolls before you've even managed to gather the materials for a single G5 roll, and a good G3 will likely be as good as a typical G5.
Farm materials for something if you can see a meaningful difference between G3 and G5, otherwise you're likely to get several good G3 rolls before you've even managed to gather the materials for a single G5 roll, and a good G3 will likely be as good as a typical G5.