Tandem Cycling - Anyone use a 20mm adaptor on a Yakima Sidewinder?

I'm wondering if any of you have any negative comments about the Yakima Sidewinder
and more specifically if any of you have used one (or could see it being used) with a 20mm axle adapter?

If so, which (brand) adapter are you using? I don't want to watch my baby hit the highway!

Thanks!

I had to shorten our Sidewinder to fit the road bike. With the MTB (heavy Rohloff hub) on the shortened Sidewinder the fork is pulling up on the rack. I don't like that so I just carry it on a single bike carrier and tie the bike down side to side. The Rocky Mounts 20mm adaptor works just fine. Someday I'll buy a Thule/ATOC or make my own carrier like this http://willicarville.com/tripletrack/

Just saw this thread after spending two hours installing a new Yakima Pickup truck mount with a "Fork up" 20mm axle adopter to carry the Ventana (below) and Santana (left). As my pickup has a topper, I installed the Yakima aft on the bed so the bikes face to the rear. The Ventana is longer but the Santana's drop bars stick forward of the front tire more. So it was a juggling act to place the Yakima so both bikes would fit without hitting the rear window or roof. But it works fine. Considering the value of the two bikes, I would'nt consider carrying them out in the weather. This Yakima follows a Nashbar I've used similarily for 17 years.

Thanks to both of you!