I have had really good results dealing with INGOers. My results also include a fair amount of dealing with folks who don't post much and are not as diligent as a lot of us on tidy posting.I have had more good than bad. Sometimes if analyzing an ad, it is apparent that the author has poor writing skills. Although there are also just plain icky people out there.
That said, I have a handful of INGOers that I just wouldn't deal with, due to their post content. Folks that are abrasive or not helpful or don't reflect well on INGO (in my opinion,) I just pass on.