In my personal experience and from reading many messages posted within this Clip Sport Forum, the player starts to choke with micro SD cards above 32 gb memory. Here is a very useful message stream that has lots of helpful tips.
http://forums.sandisk.com/t5/SanDisk-Clip-Sport/Clip-Sport-and-200GB-SDXC/td-p/355520
Also above 2000 music files on the card, you can only play these files using FOLDER mode. You cannot control this cutoff (?)
AND, every time you use your PC to manage the SD card content, the player will refresh the music database. With larger cards and more music files, the refresh time can get kinda frustrating. I think 16 gb cards are the sweet sport for the Clip Sport (and Clip Jam).
