Best footwear for Cambodia?

In January, I'm going to be going to Chi Phat, and maybe Virachey, as well as all the other great places in Cambodia and I was wondering if I can get by without hiking boots. I have a great pair of those hiking sandals with the enclosed toes; they're more like ventilated sneakers and good for water. I also have a pair of hiking boots that I really like, but they are considerably warmer to wear even though they're lightweight.

So question: Can I get by entirely on the hiking sandals or will they not be protective enough for multi-day jungle hiking?

I would say that for the majority you will be find but for full on multi day jungle treks you will want closed toes, there are likely to be leeches and thorns that can stick into your feet, the last thing you need is an infection. Wear a good pair of woolen socks to wick sweat away.

Trail runners would be just the ticket. I had those as my only footwear for 3 weeks in SAE, including 3 day jungle treks. Surprisingly enough they are not sweaty (GoreTex) and certainly more comfortable and more nimble than full boots.

Leeches just LOVE sandals, makes their life so much easier... Even with shoes you are bound get sucked, if not so much on feet, then at least from the neck... And they will get into the shoes also.

I have a pair of light trail runner type Merrells and they do me well throughout Asia.

As dog and petrus say -

also make sure that that whatever you take you have walked them back in so that you do not risk blisters - you would be surprised the number of people I have seen at Chi Phat coming back from trecks with painful blisters because they had taken their favorite hiking boots but forgot that they had been wearing normal shoes for the last year

I wear light hiking shoes and socks everyday, everywhere in SE Asia. Even though my upper body is often very sweaty, my feet remain surprisingly cool. Be sure that your shoes are well worn in before your trip. I think a well fitting, supportive pair of shoes, and comfortable socks, are the single most important piece of gear for travelling.