REFLECTOR: Aileron Fences

[Ron N VelocityXLFG]

I was thinking of trying aileron fences to help the sluggish 
characteristics of my plane  when
it is low and slow. If memories serves me correctly aileron fences do 
just that with no speed
penalty  correct? What should I expect if I do install fences ? Is there 
a size and shape that has
  worked out best?

Almost done with phase 1. Been a long 36 hours so far but enjoyed every 
moment.

Ron