i don't buy that at all!!!! - my fasted growing zoas are very eyecatching orange skirted (two types with dif rims), followed closely by some form of what many call dragon eyes, and my morph of the AOG clan. I believe it is a exponential thing - ie- most people who have fairly common zoas have colonies of them and therefor they spread faster as there are more zoas to bud, whereas the less common or special zoas are small frags of less then 10 polyps and hence less individual budding. simple math = example 1polyp/month on a colony = 50 new ones a month a small frag = 5 a month, anicdotal evidence at best
i will admit however there is a certain acclimation period which varies amongst species/morphs - some simply are more adaptable to light/flow/water conditions and so start to spread quicker.
also i would add, i have no "ugly" zoas - why would you when tank space is so precious
