Well... you posted this a while back. (I'm sorry you're only now receiving your first reply.) So perhaps the meeting has already occurred. If so, hopefully it went well. I'm not sure what I could offer in the way of advice anyway. I think the main things are, first of all, be as specific as possible & have as much data as possible to back up your argument. And, second, stay focused on the concern at hand. Avoid allowing the discussion to veer of onto tangents. It's easy for something like this to deteriorate into a general gripe session. I'd have to say this sort of thing never really produced much of anything in the way of positive results for me. But, hopefully your experience was, or will be, better.