Newer Canon lenses have been 9- and 10-bladed.
Hasselblad's old V system lenses had 5 blades, curved in C lenses and straight in CF and later.
Fun fact for manga fans: the heavy use of Hasselblads in fashion and the resulting pentagonal bokeh lives on today in the frequent appearance of pentagons in the screentones of shoujo manga.
Is that normal or does it indicate some sort of problem?
If I were to ask an optician about it, what words should I use to explain the problem? Would they know what a "sunstar" is? Is it different to "lens flare"?
Whenever I bring up the question of corrective surgery my ophthalmologist manages to somehow change the subject. I suspect that my astigmatism has gotten so bad that lenses can't completely correct it (thus worsening starbursts), making me a poor candidate for surgery in his opinion, notwithstanding all the marketing promises out there. Perhaps we're both in the same boat if you're also still seeing starbursts with your prescription.
Rounded blades can still get a cool effect but the sunstar points look like a triangle instead of a straight line.