I'm sure it's a one off, I've used Hiflo for quite a few years in my bikes and I've just replaced the leaky one in my V Strom with the same.
Usually I give my bike a good covering of Waxoyl at the start of the winter and I degrease it at this time of year when I do the annual oil and filter change. I spray Waxoyl everywhere onto every exposed surface, wheels, forks and engine get a good dose, brakes excepted of course.
This year I didn't do that, so I suppose I only have myself to blame.