I have the Oneway curved rest and would say going to a depth of 9" would be a cause of vibration on the end of that rest. The Robust looks more supported on the entire length of the rest. I think if you turn another, you should turn two 4 1/2" deep ones instead.
Member Illiana Woodturners
That's the sasquatch of bowls! It sure looks like the wet sanding paid off...the finish looks great. Cool bowl Roger!