I just want to comment on the BIM and Taipan Portsmouth numbers. I own a 4.9 and have seen and sailed against the BIM singlehanded. The PN number is a "gift" for the BIM IMO since the BIM uni with spinnaker is rated slower than the Taipan uni W/O spinnaker! The BIM is fast, especially upwind; and downwind, with the spinnaker, it is no contest vs the 4.9 (w/o spinnaker) but both sailed uni (w/o spinnaker) downwind the 4.9 has an advantage. To my knowledge no one has sailed a uni setup (w/ uni specific cut mainsail) 4.9 w/ spinnaker against a BIM w/ spinnaker (and I and Mark are the only ones to have sailed with each other on the same course at the same time uni only that I know of).
It's also worthwhile mentioning that a 4.9 can be retrofitted under F16HP rules with a different mast/mainsail including one similar to that found on the BIM 16 and the BIM can be fitted with a larger spi (presuming the mast would handle it) than the one that was being used on it in the past (although there is debate still about the merits of larger spinnakers on these lightweight boats and we are all still trying to find out what the "hot ticket" is- the 4.9 with the big- 21 sqm- spi does have helm "issues" but they are less with the 17 sqm spi- the F16HP size and I'm not sure what they would be with the small BIM spi so sort of comparing apples and oranges there).
In my mind, if you are talking going uni only, then the "big" advantage of the Taipan over the BIM is largely negated. Whether you go with the Taipan or the BIM 16 you will end up with a great boat that will be as fast or faster than your current boat on the water and MUCH easier to setup/trailer/move about/right/etc.
Welcome to the class!
Kirt