After about 4 months of experience on riding different race boards, I found there is a world of difference in the stance and the riding comfort for the different boards. When I first started to use them this past July, I was on my first hours on directional boards. I found that many hours of adaptation were required before dialing in with the board (a Rogue Wave Race 5'8"x20" or 173x51cm). Riding the boards flat and not putting so much back foot pressure required a little getting-used-to. Since then, I have tried a few other race boards. Some of them I liked, some others, well, not so much.
Many people I kite with also tested the different boards. Most had little or no experience on directional and race boards. The most common mistakes I saw, and I did the same when I started, was to much heel-side and back foot pressure applied on the board. This is clearly due to years of twip-tip use.
The boards I have tried:
North Race Ltd 2009 - 163x45cm, twin fin 15cm, 22°
Rogue Wave Race - 173x51cm, quad fin on Probox boxes, front 20cm 8° cant, back 15cm 8° cant
Rogue Wave Race - 173x51cm, quad fin on US (A-type) boxes, front 21.5cm no cant, back 15.5cm no cant
Airush Monaro 2009 - 170x46cm, twin fin 15cm 11°
RRD K-Race 50 - 180x50cm, quad fin, front 22cm 35°, back 15cm 15°
The Probox boxes on the Rogue Wave Race were experimental and were not solid enough for the job. They would loosen up and the fins would start to vibrate. The grub screws did not like the strong, outward lateral pressure applied to them. Hence the replacement with the sturdy US boxes. This board also has a bit of convex, hence the fins are slightly angled outward by a few degrees one relative to the other.
Initially, most people find the North, Airush and RRD easy to ride. I feel these boards are more accessible to most as they are quite forgiving. They can be ridden on the edge and all required more back foot pressure, something everyone is used to and comfortable with. On their first attempt, all also find the Rogue Wave difficult to dial-in and jibe.
After gaining some experience, people started to find the Rogue Wave more and more comfortable and easy to jibe. With proper fin positioning, it is possible to ride this board with both legs pretty much fully extended and with the body leaning back, absorbing the chop with the entire legs moving up and down, as opposed as with the knees only. As of today, this is how I ride the Rogue Wave, working the board pretty much equally with the two legs This position is so comfortable that I can ride it for hours at a time.
Today, I find the North Race Ltd 2009 too unstable. With a twin fin setup, I find it does not track or keep its line very well. For the RRD K-Race 50, the fins are very much far back under the board. This requires the body to be positioned towards the back of the board, hence the back leg must be bent so much that I get tired very quickly with the board. This board is also too heavy and thin compared to the other ones. As for the Airush Monaro, I initially felt it was a half-assed surf/race board, but it is actually quite pleasant to ride as a fun board. It does not race well, but certainly does better in waves than true race boards.
Looking at the many videos of top notch racers, the question that comes to my mind is: is there such thing as an optimal stance on race board. As I wrote earlier, I find the fully extended leg stance is quite comfortable because of the balance of the weight of the body is distributed almost equally on the two legs.