does GA and GP behave somewhat predictable then?
Couldn't it, if you are unlucky, take a very long time to converge?
Roger Alsing (who was the original author and inspiration) did later an optimized compiled parallel version that was able to get Mona Lisa in 1 minute 34 seconds (on a 64 bit 4 core machine).
http://rogeralsing.com/2009/01/04/scaling-clustere-evolution...
Also there are supposed to be some efforts to run it on GPU, which should be even faster.