Andy,
I have flown them all.. No issues on the fins..
I have flown the booster 3 times.. (its a tick scary). There has to be NO WIND.. 1/4 mile walks to recover if there is...
The Ascender is my favorite.
The E16 has a nice kick to it.. the F15 is a tick softer...
I have never seen the flutter by fly... (I made a rhyme)
Grim