Should you hire a tuk-tuk driver or guide for Angkor?
A tuk-tuk driver is often worth it because Angkor is spread out, hot and tiring. A guide is worth considering if history matters to you; otherwise the main win is having transport that does not drain the day.
Answer
Angkor looks simple until you are moving between temples in heat, with water running low and another long walk ahead. A reliable tuk-tuk driver keeps the day from becoming a transport puzzle and lets you spend energy on the sites themselves. A guide is a different choice: less about convenience and more about context, stories and knowing what you are looking at. Some travellers want both; others only need a driver and a good route plan. Either way, choose for the kind of day you want, not just the cheapest quote.