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Just a few notes on my impression of how my sukhoi flies.

The bad stuff first:

The sukhoi has quite severe rudder to elevator coupling. Give it some rudder and it pitches towards the belly (nose down). This effect wasn't so bad when I first flew the sukhoi with a more forward cg.

I'm just starting to learn how to fly Scale Aerobatics and I probably haven't got the sukhoi set up very well. The servos I'm using are Futaba 3001's and I originally set up the control throws to be really huge. So for normal flying I use the dual rates to reduce the servo throw, but I think that this is affecting the precision.

Because of the rudder to elevator coupling I have found that it is very difficult to take off and land in cross winds. I found it extremely difficult to use the elevator to keep the plane from nosing over. Maybe it would be easier if my elevator wasn't so sensitive around neutral.
Also I think that the long landing gear probably makes the plane more likely to nose over in a cross wind because of the extra drag induced on the wheels by the side force, and the landing gear being long and having quite a bit of leverage.
I fly from a grass strip, maybe the long landing gear wouldn't be as much of a problem on a tarmac or paved strip.

With the cg in the forward position marked on the plan, the plane had a very gentle stall; it just sort of mushed forwards. But it would pull out of dives and it needed quite a bit of down elevator to maintain level flight while inverted. I took the cg further back and at the rear most position I found that I had to be careful with the elevator to avoid tip stalling the sukhoi, but the sukhoi still needed some down elevator when inverted (I didn't take the cg so far back that the sukhoi would fly inverted with no down elevator). At the moment with the cg in the middle of the range, the Sukhoi goes strait down on downlines, only needs a small amount of down elevator when inverted and it doesn't tip stall unless I get it really slow on landing.

There is a small amount of rudder to aileron coupling but not much. I don't have a computer radio so I don't know if it would be easy or not to mix out the rudder to elevator and aileron coupling.

 
The good stuff:

The Sukhoi tumbles really well, lomchevaks (sp?) are neat, as are knife-edge spins and normal spins and snap rolls. I don't do much tumbling manoeuvres myself though except for the odd lomchevak, most of the time I practice flying the sportsman IMAC sequence.
The Sukhoi seems to fly very lightly, even though the wing loading (on mine anyway) is 24 1/2 oz/sq.ft.
With the SuperTigre G.90 the Sukhoi has heaps of power (I am running it on 20% omega oil and 80% methanol, no nitro), more than enough to accelerate out of torque rolls etc. A decent lightweight .60 would probably be an ok choice of engine for the Sukhoi, especially if some of the formers etc. were lightened.
One of the things I really like is the fact that the Sukhoi looks like a Sukhoi, both on the ground and (depending on how I fly it) in the air.
Last of all, the Sukhoi stands out amongst all the Extras and Caps etc.

I'm glad I built the Sukhoi, I think if I build another one I'll cut more lightening holes in the ply parts and maybe try to make or get a lighter muffler. It'd be good if I could do something to reduce the rudder to elevator coupling but I'm not sure if I want to deviate from scale. I'd also set up the controls with not so much throw.

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