I've been there too, it's an awesome place :)
The insect situation was ok during the day, but once the sun set you wanted to be inside. Very hot and humid though, I was there end of July and although we did rent bikes and travel around on our own it was hard to do so without sweating profusely!
@rainman I was there in January, evenings were cold and we had heated beds,so my memories of the evenings are sweet :) . I went for the river cruise by public bus and returned by bike, it was an amazing experience navigating with no one around speaking a word of english.