I think the best way to 'acustom' yourself to rockets is the 'practice, practice and more practice' method using the Training X as an aid. You can get that in the Training Arena or offline if you set it up.
Set up offline by:
clipboard to SETUP > ARENA SETTINGS > FlightModeFlags.
Enable the 'bombsights' and 'gunsight' and you get all the 'training Xs' to help your aim.
After awhile, you can nail gun emplacements from 1.5k out.
They do drop way more than guns so an angled approach helps to increase the range.
Just my two cents,
fuzeman
Also, each different rocket type will act different, of course.
Like a P51s will be slightly different than a Typhoons and so on.
I think that may be more country based than plane related.
A P51D rockets will behave similar to a P47s or p38s.
The P51B however may be in that 'different' catagory.