Are you in Europe? That sounds like PAL or SECAM. Over here, it is recommended to go from 60 Hz to 120 Hz or 240 Hz because it's an even multiple of 24 fps, so the maths are easier. Going from 50 Hz to 100 Hz doesn't make the maths any easier (because it's still based on 24 fps), so you lose that. It could still theoretically be good, but you really need to go into a store and see for yourself. Look for a scene where they pan side to side. If you can't tell the difference on the material that they're showing you, then I wouldn't get it. They're probably not showing it to you for a reason ("most people can't tell the difference" being my guess).