I haven't fallen in the shower yet though I tend to bump into corners of tables and desks - I have the bruises to prove it.
Hubby uses a shower chair now after his stroke last year but I remove it when I move into the cubicle - I'm not there yet!
Your grab bar looks solid and strong. I looked for grab bars online last year and the reviews horrified me - many shared stories of it pulling out of the wall. So far hubby has managed with me as his personal grab bar when he climbs out to reach for his walker. When the time comes that he needs one in the shower, I shall keep yours in mind.