I experimented with this for the first time, Italian meringue version. It potentially offers these benefits:
1) Completely white.
2) Milder taste than buttercream so as not to compete with the cake.
3) Lower calorie, since there is no fat.
4) You can torch the exterior to get a really cool look.
It fulfilled all these requirements, but I ran into these issues:
1) No way to do a crumb coat
2) Limited working time to get the frosting applied, after which it becomes uncooperative.
If I were to use it again, I might consider a buttercream crumb coat (maybe with a complementary flavor) to be topped with the boiled frosting, giving me the best of both worlds.