What you want and the length of your trailer make it a tough decision IMHO. I had a 1966
22' Safari with a vintage rope awning, three poles, heavy springs on the tension ropes. That awning was able to withstand the winds of the OBX in NC when all others with their Zip-Dees were running to take them down. If you don't mind the setup of the old school system, the vintage rope awning system is the way to go.
With that said, a 24' trailer, you're starting to get to the upper limit of a vintage rope awning (IMHO), I think at that length you're at four poles, but could be wrong and it does normally require two people to get it setup quickly. But they still look great and will hold-up to the winds. A Zip-Dee on that length of trailer is no-fuss, one person operation, setup in less than 5 minutes, even if you take your time, but will never hold-up to the winds of a vintage rope awning. Plus with the Zip-Dee, you never have to worry about being on a spot that will not allow you to drive stakes in the ground.
I can tell you this, I use a Zip-Dee on my 1966
Overlander, and 1996 34'. I use a vintage rope on my 22' 1956