I ran some numbers on the static stability of the two tails many years ago. The larger tail buys you about 1.5 inches in aft CG range for the the same static stability. The CG range was never officially changed, so if you stick to the published CG range you simply pick up more stability. Lancair did open up the forward CG range given the improved effectiveness at low speeds.
Chris Zavatson
N91CZ
360std
www.N91CZ.com