The conventional offline UPSs are not voltage stabilizers, nor are they better. The only voltage stabilizing they do is switching to battery backup if the voltage is outside a pre-set range. To avoid switching to battery backup too often and shortening the battery life, this range is usually set pretty wide, like 180 - 260V. Only online UPSs continuously convert AC to DC to AC and keep the output steady at 230V. They are not cheap - the SmartUPS range is the online type I think and prices for those start above 10k.
Electronics these days (like LCD TVs) run off lower DC voltages and use an SMPS (similar to the one we use in PCs) to convert AC to DC, and these have a wide input voltage range (IINM mainly so they can function in both 110V and 230V supply countries), so you should still be ok.
However lightning/surge protectors are sacrificial, i.e. they protect other components by absorbing all the energy themselves, and getting damaged in the process. The varistor mentioned in the LG brochure above is one type. Think of it as a one time fuse. So you're better off keeping it external to the TV because it's cheaper to throw away a surge protector than to open up the TV and replace this component, or worse assume its still functioning and not have it protect your TV the next time there's a surge. This is another flaw with surge protectors because most of them do not indicate if the varistor is still functional.
