Hi John
Here are some fotos of my BREEZER and some figures from flight-testing it.
Position on Wings:  95mm (7.3% chord) behind leading edge
spaced 17 times 60 mm, beginning 80 mm inside from wingtip, then 23 times spaced 90 mm.

 I tried them on the rudder (17 spaced 30mm, 100mm in front of hinge line, starting 80 mm under top of rudder. I placed them horizontal at cruise attitude to make them becomming effectiv at higher angels of attack (i.e. at slow speeds).

Just as you experienced before on your Savannah I didn`t notice any improvement in ability to slip.
Though there must be an effect:
Without VGs - at power on stalls the aircraft turns left at high angels of attack, even with full right rudder.
With VGs - I always was able to keep the aircraft straight with right rudder input.
(compensating the prop torque at very high angels of attack)

 Idle power    no flaps
without VGs                IAS 64 km/h
Aileron: starting tubulence, almost ineffective
with VGs                     IAS 60 km/h - 6,3% IAS
Aileron still effective, rudder still effective

 Full power            no flaps     
without VGs                IAS 57 km/h
Aileron: starting tubulence, almost ineffective, ¾ right rudder.
with VGs                     IAS 48 km/h - 15,8 % IAS
Aileron effective, rudder effective.

 Idle   power                   full flaps (45°)      
withoutVGs                IAS 52 km/h
Aileron: starting tubulence, almost ineffective, full right rudder to keep aircraft straight .
with VGs                     IAS 52 km/h
Aileron effective,  rudder effective.

 Full throttle         full flaps (45°)
without VGs                IAS 48 km/h
Aileron: starting tubulence, aileron almost ineffective
Even with full right rudder the aircraft turns left, no way to keep it straight......
with VGs                     IAS 40 km/h- 16,7 % IAS
Aileron still effective.  Right rudder now overcomes left turn of aircraft. Maybe due to VGs on rudder???

 The pictures of airflow are documented by video.
A small dentist mirror placed in front of the video lense shows the airspeed indicator. 

       Holger's Breezer with VGs, ready for tuft testing.                             Note the extreme angle of attack, in reference to
                                                                                                                                 the horizon, and the ASI at 40 km/hr!

Holger, Germany

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