If Singapore is similar to Australia then the normal HD "720p" tvs whether they're LCDs, LEDs or Plasmas will be quite sufficient for cable TV and general broadcasting since their limit is only 720p at the moment. Watching a lower resolution broadcast than what the TV is intended for will always give you less detail especially if you try to magnify the picture with even larger screens (like in your case a 50" screen).
However if you watch a lot of BR and/or 1080p streaming media from an internet or media device then you should get a Full HD TV.
Bear in mind that there's no point in getting a 50" screen if your room is tiny or you sit really close to the screen. Not only do you need to pan your head to see end to end, but you're wasting a lot of power and "visual estate" like that. Furthermore, you will be watching pixels play with each other going on and off and changing colours than actually watching something.
You have to be at least 10 metres or more away from the big screen to appreciate 1080p.
10 METRES:bsmilie::bsmilie::bsmilie: HDB where got so big