I'm not much of a boar fan, as their quality when I first started shaving (50+ years ago) was pretty dreadful, and most aspired to own a decent badger brush.
I like synthetics, and have several high quality badgers and horsehairs, but the synths. top my list of favourites. However, some time ago, I bought a Semogue Excelsior boar and an Omega (model unknown, as I think the label wore or fell off). Neither had much use until recently, but on a whim I started using both again. I've been using them with P&B and Nanny's in a couple of Giles Shaving bowls, and in doing so, have given them the sort of beating unthinkable with badgers/horses.
Both had stayed stubbornly unbroken, the Semogue a little less of the two. However, I have been gratified to find that the brutally harsh treatment I've given them has caused the ends to split nicely, and they are turning into decent brushes. If I can stay with them, and not get lured away by the other types, they should break in fully and well with another dozen or two uses apiece.