I found that the Rocket was easy to get used to and very forgiving in the gybes, but probably a little predictable and I felt that it was lacking that bit of mongrel that (I believe) typifies the average slalom board, but after changing to starboard, RRD, F2, I believe the whole exercise could have been achieved by just changing the fin!!

I sail in a mostly weedy environment and predominantly use weed fins and my search for the perfect weed fin goes on. But, by using a slalom fin when the weed clears up the board behaves completely different. I found the inner mongrel, if you like.
There's always a trade off, a freeride board won't go as well as a slalom board, but a slalom board won't be as forgiving as a freeride board. I guess, for me, comfort takes precedence over speed, and if you sail comfortably your speed increases.