@Marakesh I too was very worried about taking AIs. I started Letrozole 1/8/17 and yes a bit of joint stiffness but basically has been ok. I took Krill Oil capsules suggested by oncologist from the start - no idea if it helped. I walk daily for 1 hour and find it helps a lot. The downside for me is a sharp increase in my cholesterol which I try to manage eating rolled oats every morning and eating low fat - I have tried statins some years ago after a TIA( mini stroke ) but found they caused problems for me essentially memory issues.I suspect those who have undergone chemo may have a tougher start on AIs because of it.
My experience is my body adapted reasonably well. I had a few hot flushes but at 64 am well past menopause anyway and been there done that - younger women may find hot flushes more problematical.I was also osteoporotic with an osteoporotic fracture before starting Letrozole and have 6 monthly Prolia injections which have also not been a problem.Guess I’ll know the impact of Letrozole on my bones next year when I have my bone density checked. Yes like others vaginal atrophy is occurring making Pap smears less comfortable and some urine leakage requiring an ordinary daily panty liner - the latter however may be a by product of a twin pregnancy at 47.
Hope this helps.