RE: my lost in build quality noise comment...
This was not intended to be a comment on sloppy workmanship, but a quick & dirty way of saying details/fit/finish/etc will typically make more difference than the wing planform, on performance. Example:
The *claimed* top speed of a Lancair 360 (200 HP) is 260 mph, though I haven't seen many owners claim that high a speed. The fastest Hershey Bar wing RV6 (180 HP) that I'm personally aware of, built by Tracy Saylor, topped out at north of 235, in closed course races. The fastest RV4 (200 HP), built by Dave Anders, was tested by the CAFE Foundation at 250 mph. IIRC, he's gone significantly faster than that in races; he's constantly changing stuff on the airframe.
Now, speaking as a 3-time RV purchaser and current builder, I think the Lancair is a truly stunning airplane; far better looking than any RV. To get top speed roughly equal to a well-executed RV, it gives up a *claimed* 8 mph in stall speed, at 63 mph. But with 73 sq ft of wing vs 110 sq ft for the RV, I kinda suspect the numbers are fudged a bit on the low end, as well (likely closer to 75 than 63). So if you give the Lancair enough wing to meet the RV's stall speed, the top end for a really clean RV will be as high (possibly higher) than a typical Lancair, which should be, out of the box, near-perfect aerodynamically, with that tiny wing and perfect looking fuselage.
So....performance based on wing planform choice can easily get lost in build quality noise. ;-)
On the RV7 rudder issue: Some -7 builders have opted to go back to the smaller -8 rudder, preferring its control harmony over the larger -9 rudder. Van never said that the -8 rudder was unsafe on the -7; just that spin recovery was not quite as quick they wanted for customer-flown a/c. It's worth mentioning that the factory cautions about playing with spins in all their models. They don't tell you not to do it, but to expect...exciting... spin rates.
edit: Not much to show yet on the rotary (Mazda Renesis) front. The FWF is 'done', but the plane hasn't flown. So as they say about how long battle plans survive...
Charlie