It depends. What generation is your KJW? The first gen's (and possibly second... I'm not clear on when the divisions between generations occured) were based more upon a WA design, and they will NOT take TM mags. However, current KJW's are supposedly TM-compatible, and should take TM mags. Please don't hold me to that, as KJW's specs/notion of "TM compatibility" are kinda screwed up. But yes, if possible, TM mags will give you much, much better performance.
Perhaps a picture of your current KJW mag(s) would be helpful?