For laryngeal checking, which one is better between rigid endoscope and flexible endoscope?

Throat is always stuck, which one is better for checking? Rigid endoscope or flexible endoscope or ultrasound? Some said: Ultrasound is too expensive, Rigid endoscope is harmful for laryngeal, flexible endoscope is better. How about your advice? Thanks.

I wasn’t given a choice and had the flexible endoscope.It was a bit uncomfortable but the whole process took less than 5 mins.