I don't have a problem posting negative information about a company if I've had a payment issue and have tried in good faith to resolve it without success.

Having said that, however, one needs to be very careful about making subjective statements.  My attorney tells me that truth is a complete and absolute defense to a claim of libel or slander, and one should make sure to have plenty of supporting documentation to substantiate any negative statements made.  I, for one, am not afraid to tell it like it is.

But, that's just me.

Regards,
Scott Perry