<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Someone on the RV.net said we couldn't use a non-proportional system so I'm trying to find out what to use. </div></BLOCKQUOTE>
Everyone's opinion on the forums, especially RV.net., IMHO is worth exactly what you paid for it. Nothing. Including mine.
I have never heard of such a thing. The toad had no idea what is pushing on the brake pedal, proportional or non-proportional.
However there may be an issue with a particular brake system.
You are wise to investigate the various systems.