I also have the Sitex SP-70. If your steering is really tight, it works good. For the first couple of years I had the boat, the steering wasn't tight (even after $5K spent with a certain repair yard with the initials AMS), and it was hard to tune. The Sitex takes some getting used to adjusting for conditions, but once tuned for the swell direction, I have slept for hours on the way back in, while the co-pilot stared ahead, and come back out to see us splitting the Islands from 70 miles out, hands never touched the wheel.
Glenn (Wizard)
"The Reel One"
26' Billfisher