OK, first of all, I should preface this question with the statement that I am extremely well versed on how a flybar works, how to set one up for a stable hover, generally about the effects of weights and shape of paddles and flybar ratios etc.
Just so we don't get bogged down going backwards with stuff we already know.
Here's the question, put as simply as possible;
Keeping everything else the same, by going to a longer flybar we WILL gain cyclic response due to the faster speed the paddles are travelling.
So do we lose something elsewhere? (setting aside for the moment the extra power it will take to spin the longer flybar).
Do we only gain (faster cyclics) or do we lose somewhere else?
There is a big difference in length between for example the TRex 700 flybar and some other .90 size flybars. Obviously there's a limit to how long you'd want a flybar, it would be like a wet noodle at some point :-) So I'm not talkin about going longer than the longest I know of (Trex 700). The Trex flybar is about 580mm compared to 480mm on the stock Robbe Futura / Milli flybar.