120HZ is fine… There really IMO is no real difference between 120/240HZ its more of a marketing gimmick. The TV’s at the core is still 60HZ, all the 120/240 is their ability to smooth out the picture, which in most cases ends up making it look fake and giving it that “soap opera” effect.
Basicly the TV’s put in more information then whats being given to smooth out the picture. I personally hate it, but regardless the difference between 120/240 is really not much of anything and more marketing then anything else.
If your not a picture snob then this TV would do the job just fine. Sharps always tend to have a very nice picture.