Well, it is amazing what a little braze can do but I would say that optimally that fillet should have been bigger.
I build up a fillet around things like this in silver. It looks better and give more reinforcement. BTW I typically use bronze for brake studs. I have silvered them when attaching chrome for repairs only. Also some stainless bits.
You have inadequate wetting too in a spot on the left hand side. You should see a little fillet on the inside too.
Ah, it's only a rear brake. Won't kill you if it lets go
Have fun.
Dave Bohm
Bohemian