Honestly, Bintan is a shithole. Northern part that so called 'resort territory' is no go for an ordinary indonesian people (which, if I'd be an indonesian, would piss me off on a grand scale) and presented as 5* luxury hotels on booklets.
In reality - it is decayed buildings, really bad and extremely overpriced food at site - $6 for a can of coke and people got food poisoning after eating mee siam which was $22 per portion. 'Perfect beach' is just 200m stretch of sand which is brought from other parts of indonesia and right after it ends, you will see pile of trash accumulating there.
For indonesian part of that island it like Batam but imagine more gloomy, more pollution, dirtier, smellier and electricity goes off several times per day. And if you are male who is easily recognised as non-local, then once you get in Tanjung Pinang, as soon as you are out on streets on evening, some shady people will come and ask you if you want boy or girl.
So, yes, for reality check and anthropology research - worth a trip. For anything else - don't go.