A couple of years ago 90% of GU10 led would not dim with a conventional dimmer. My experience today is 95% will dim with any sort (trailing or leading edge) dimmer. My own house has 14 dimmers ( all different makes) , none of which i have changed since i went from MR11 (12v halogen) to GU10 led.
I also think the latest range of COB, GU10 in glass shells are the best , You can hardly tell the difference between them and halogen.