Thanks for all the replies. Looks like there's a good mixture of opinions. Indoors I always reach for the 50 (or wider) as focal length is a limiting factor but outside am always drawn between which lens to go for. Head and shoulder shots I tend to pick the 100 L, but for full body im never sure which to pick... For those using manual focus lenses are you using liveview on a tripod? Seems a difficult task to get sharp focus on an eye when using the viewfinder from a couple of metres away?
There's been a few comments on the bokeh, but i'm interested in hearing more views here in relation to the 50mm stm. I've been very pleased so far with the 50 stm, but going through my photo's i'm not sure i've really tested the 50 stm in hard conditions (e.g foilage in the background).