Can I buy one of the EF 100mm Macro lens instead of EF 85mm f/1.8 USM?

ms18 wrote:

I use EF 50mm f/1.4 USM with APS-C to take photos of portraits and Indoor sports. Now I'm planning to replace it with a lens with a 5D (Later upgrading to either 6d or 5d mk iii). Main reason of this replacement is inadequate focus speed and the next is 50mm f/1.4 is not good wide open but that is the depth of field I would like to have in some portraits. Next any way i want to move to full frame for indoor noise performance.
I was thinking about buying a EF 85mm f/1.8 USM. But later on i was planning on one of the Canon 100mm macro lens. Either the L version or Non L version. The 15mm focal difference is not a problem for me. I can adopt. I like the bonus feature of Macro. But my worry is how fast is the auto focus? The very first reason for this upgrading is auto focus speed. If the autofocus is capable same as EF 85mm then I would like to go for 100mm macro. Also let me know if there is a AF difference between L and Non L in 100 macro.

I think an original 5D with a 100 macro will be challenged at shooting indoor sports.  I haven't shot badminton but have to think the movements are pretty fast, particularly the swings with the racquets and birdie action.  5D is not known for fast action accurate focusing and the 85 1.8 is faster to focus than the 100 macros.  Also don't know how bad the lighting is in the indoor venues you are shooting but if it's not too good the 1.8 will of course give you more advantage than 2.8.  You can find used 85 1.8 lenses for pretty good prices and continue saving for the macro.