How do sativa`s flower compared to inica`s

My last grow was with snow white, which is mainly indica... but i am now growing AMS, AK-48 and white widow and have noticed that the buds are taking much longer to develop. My snow whites buds were really big by week 4 but these are all half the size. Is this normal and just because they are more sativa than indica? If not maybe iv cocked up by flowering them too early... With the snow white flowering really slowed down by week 5/6 im just hoping these dont go the same way otherwise its going to be a bad harvest and i will have to start building a wickerman....
Mite post some pics tomorrow if required...

According to my research - sativa strains take a about 16 weeks to finish budding compared to 10 for indica. Also, sativa buds are fluffier then indica i.e. won't weigh as much. This is why I have avoided sativas like the plague.