Personally, I'm not a fan of reading works that overdo swearing. It often makes the writer seem stupid...it makes him/her look like they've run out of ideas and are just filling in spaces with swear words....I'm speaking specifically about fuck and cunt...all the other swear words (shit, piss, cock, bastard, arse...whatever) are pretty much commonplace anyway. I don't find them to be swear words at all. But in the end, the marking is subjective...so you could get a really open minded marker, or an uptight traditional one...so IMO, you're running a risk.
The less controversial the better in that sense...but if it's entirely without controversy, you're not exactly pushing the limits of your medium. Unfortunately, as with English as a whole...everything is subjective.