Letrozole vs anastrozole

Thanks to you all. @Deanne if you wouldn't mind, let me know what your onc said. It will be interesting. I've been on letrozole 14 months , wasn't on tamoxifen as i was post menopausal. I can relate to painful writing! I find typing easier. Every now and again my thumb joint does a little 'click' and it frees up so much almost as if it had been dislocated and then put back in place. This happened last night.  It doesn't last though. 
@Vangirl i had constant hot flushes for a long time mainly at night but they have now all but disappeared. No foggy brain or tears though.