are smaller plants healthier and better quality than bigger plants?

it all depends on how its grown. weather, the enviornment, all that goes into it giving you quality buds

for the average grower though i would say yes a 4 ft tree is better. one that is 10 ft would need a lot of extra lighting on the sides and how take a lot longer to grow. A 4 ft plant would have more dense buds all throughout the plant where as a 10 ft plant could get fluffy the further it is form the light.

I agree with farel2. Smaller plants are always easier to work with and usually have less problems. It depends on a lot of factors though too, sure. As a rule though, smaller plants are usually indica dom & taller sativa dom. Indicas get bushy and get FAT buds. Sativas tend to get airy and wispy buds. You can get a bigger over-all yeild from a 10 ft sativa as opposed to a 3 ft indica, but I would only recommend growing this huge sativas outdoors where they "belong". You can make either plant healthy, its just a matter of which is easier to work with (espically indoors).