Taiwan’s advantages: safer, cleaner and more organized in general; higher standard of living; greater concentration of traditional Chinese culture forms not destroyed in Mao’s Cultural Revolution, such as Kung Fu, Chinese medicine, temple culture, etc. Also, here you can learn traditional Chinese characters. Higher pay; generally better food (personal opinion); interaction with Taiwanese less based on your wealth level as theirs is OK, unlike China where - I have heard - the difference between girlfriends and “working girls” is more slippery. Taiwan has excellent access to natural areas from urbal areas due to the fact that it is mountainous and earthquakes and typhoons make construction on the mountains unsafe; easy access to the sea; friendlier people - in general.
China’s advantages: cheaper, larger and more varied; more of a global power and less an isolated anomaly; more cultural variety; Tsingdao beer for 2RMB; stronger sense of national pride; stronger feeling of a glorious future.
These are just a few impressions.