The 50-110 is my most used lens. It is heavy so difficult to use handheld but I do. I also have the 35,80,100,150,210&300 but the zoom is used most.
It is fabulous in quality, actually so good you almost would not believe it. It is better than some of the fixed. Definitely better than the 80, virtually on par with the 100 (which is very good) and some people that have or used to have the 50 claim it is better than the 50. I have never used or heard about the macro.
Again, it is heavy and will wear you out when using handheld. On a tripod, it is definitely the must have lens.
All IMO naturally and with my way of working which is about 50% fixed and 50% handheld currently.