Letrozole or Tamoxifin?

Hi Fellow Hormone blockers :-)  Really need some advise , my situation 60yrs old with thin bones  Had 15cms DCIS removed via mastectomy and a 5mm invasive cancer. The oncologist is giving me the choice between the 2 drugs for 5 years. If I was to go on Letrozole it will thin my already thin bones so would need to go on a drip 2 times a year with a bone strengthening drug in it also need permission  from the dentist.  Tamoxifin apart from the similar side effects it also can cause blood clots and uturus cancer, Im really conflicted. The oncologist is going to mail a lot of material out to me then in a months time we will make a decision. I really wanted to talk to the real people taking these drugs, your experience and if you have been on both your preference?  Appreciate your help with this decision :-)