Board Thread:Questions and Answers/@comment-32719346-20180122185924/@comment-32271305-20180122200202

You can't go wrong by using them on LR Trunks. Due to how LRs work, raising the SA to 20 is crucial.

Unless you're planning on using the new Vegeta a lot more, and you don't feel like farming the story event to raise his SA (the grind is horrible in this case, even though it's still a farmable SA). You should always raise the SA of the units that you want to use the most, so there is no right answer, it all depends on what you want to do.