OK bloggers the following is only my opinion and it is up to you whether you pay attention or not. The way I approach all paid tasks is that I put myself into the position where I am working for the guy paying for the post and so I write it in such a fashion that he should be happy with the finished product. The way I look at if I piss of enough advertisers with crappy reviews and poor content my life as a paid blogger will be short lived.
If you cannot find anything positive to write about any available opportunities then don’t take the task. Just keep in mind though that there are ways to work in your opinion without kicking the crap out of the advertiser. Take gambling for example. I do not agree with it per se but I do not believe it is evil so in my posts I work in the fact that people should be careful when gambling so that they do not lose more than they can afford. The way I look at it if I don’t do the post someone else will and they may not disclose any such warning.