I have both of those planes by Dave Patrick.

The ultimate has a pump for cg location of the tank and an os-160 18 x 8 moki, and sometime 18 x 6 prozinger prop.

The Extra has a 22 x 8 bambula on a brison 3.2 it needs that kind of power.

Both planes fly well but for the os-160 I would go with the ultimate. Very flat spins, blenders, harriers, stable elevators, t-rolls well with the 18 x 6 pro zinger. Imac is good if you put some more thrust into the design I have about 3-3.5 degrees on mine for cleaner up lines. I think the plane has 2 degrees build into the design. The plane is very stable at the end aft portion of the rec. balance point. I needed that for better-inverted flight.

Both planes have a very strong rudder and knife edge loops are easy with the ultimate or the extra. It takes less mixing on the ultimate for straight down the run way knife edges

do you have ballet of the sky 2001 sold by prop wash video? there is one on there flown by Kevin Miller he was very smooth on the sticks of that baby. If not pick up those ballet of the sky 2001 they deal with freestyles flying...

http://propwashvideo.com/