Is the extra cost of high quality teeth and materials worth it?
Yes, but be careful what you are paying for. The cheapest teeth are made in a mold using one type of plastic. They are simply poured into the mold in one step. These teeth have no character - they are just a solid block of plastic, so look fake and wear quickly.
Better teeth are made in multiple stages using layers of different colour and translucency. There is huge variation in the quality of the teeth made using this method. Simply being a four-layer tooth, for example, does not mean that you have a good quality tooth. Some do look very good but are still soft and will wear quickly.
The teeth I use exclusively are a three-layer tooth that looks very natural and realistic, and is the hardest tooth available, resulting in very good wear-resistance.