I learned how to 'perfectly' juggle them in one day and they were great! The flat side doesn't bother me at all. They're slippery little MFS, but I love them. (Edit) Literally after 2 days of use, the flat side came out. I glued it back on but it kept falling out. I'm 14 too and can barely hold two at a time, they are quite large. not super good ngl