Very much like you said I was very reluctant to go with old "50Hz" technology.
I mean my last TV lasted 7 years. (still not long enough in my opinion!)
But I have yet to find a single reason to go to 100hz screens. Apart maybe from flicker.
If you search the TV forum's which I am sure you have. Not many people say "I could never go back to 50hz screens".
In the end I found the whole expericence of buying a new TV rather painfull.
If it wasn't hard enough to choose a TV format such as Plasma or CRT. Then its a question of 50hz or 100hz?
Then when you are on the forum everyone seems to be moaning (quite rightly) about problems that they are having.

Maybe I have become too fussing since my last TV?
In the end you should just go with what you like best.
I am not a gambling man so maybe I just chickened out and went for something I was famillar with.
However after a intense 2 week search I still feel I went with the correct choice.
Of course this could all change in the near future!...
Good Luck!