I have fine white silica sand in all of my tanks and have done for years, and have never had a problem with it. Because it is so fine and soft, it also makes an ideal substrate for bottom dwelling fish with sensitive/delicate barbels like clown loaches and corys, and the sand doesn't trap waste in it as easily as gravel so the tank will stay cleaner in general.
You should wash it before you put it in the tank though, as it can be kinda dusty.
The only drawbacks with it that i can say are true, is because it is so light, big active bottom dwelling fish like full-grown sailfin and common pleco's may swish it into the filter if the filters are sitting on the bottom of the tank on the substrate. If you go for a light colour silica sand (since it comes in almost every colour under the sun), waste like big fish poops will stand out starkly on the substrate if you do not have strong filtration to shift the waste along.
But for all the benefets this substrate has, i would say it is definately the most ideal and preferable aquarium substrate i have ever known or had .