Bikinis Over 40, 50...when is it not cool?

Hi there.  I am prepping my Bikini Boot Camp course.  I will teach a 6 week, 2 times per week Bikini Boot Camp to gear up summer.  Although given the foot of snow on the ground right now, it is hard to imagine bikini, shorts, or anything that would expose flesh to air.  But it will come and who's ready to shed the layers and reveal their tanned, toned, bikini ready figures?  Not I!  I do these fitness courses to light a fire under my own glutes.

Now for the Big Question:  Are Bikinis appropriate for women over 40, 50 and beyond?  First of all, I wonder why is this even a question, but no doubt you will find it discussed on the Internet every upcoming summer.  I am of the mind, wear what you want and makes you feel good.  But if you scroll down to the comments section of these articles you will get some strong opinions.  Maybe I should just stay out of the comment section.

I live in Europe and women often go topless from babes to grandmas.  It was a little unusual at first to see such boldness in every size and shape, but now I think, Right On!  The confidence is inspiring.  There is certainly less excruciating attention to perfection and what is appropriate beach attire over here.  I happen to like it and it has relaxed my own focus on worrying about every little figure flaw.  But that doesn't mean I am throwing in the towel and marching out to the beach without a care.  I'll be honest, I want to look good in any swim suit and I happen to like wearing bikinis.  If I am not perfection personified that's OK, I'm fit, healthy and I feel good in my bikini.

What do you think? How old is to old to a bikini?