I am not sure if the Marantz version ever introduced the 'Duration' setting for an IR code. I know the latter 7000 versions did. This featire was how the IR length was corrected.
The reason I suggested a 7000 instead of RC9500 goes back to a change in the marketing from the Classic line to the NG line.
In the days of the TSU1000/2000, Marantz paid for a differentiator for the RC5000/5000i such that they could do multiple page jumps but no beeps, etc... As a result, Marantz version's feature set was more robust/flexible than the Philips version's.
However, with the NG line, Philips held features close to the chest and IMO, Marantz was not willing to pay for the prime features and as a result, got fewer firmware updates and editor revisions. So, the 'Duration' might not be available as this was one of the things Philips added near the end of the run of the NG remotes.
Back to your original question. On the NG line, the send may be slower but was something I learned to live with. I no longer own a 7000 but I do recall lots of issues and much of my experience with them has been documented in my many posts here.
