The VGs changed the plane by 4-6mph on stall speed. The new stall speed is 41-43mph was 47-49mph and you have the control until then, but before you lost the aileron control at approximately 52mph...... 

Very excellent results!

 

My brother flew it for the first time after the VGs came on and he couldn't believe how much it changed for that amount of money and little time to install.

 

The instructions said put 15 VGs from the wingtip at 60mm separation and there after you put it on by 90mm separation but we put them on at least 2/3 of the aileron, approx 25 VGs from tip with 60mm and thereafter with 90mm.

 

This is with full flaps and a little power on it. One person on board and full fuel 166ltrs/44usg.