All three will work well as a drying aid, but the amount of water on the surface prior to wiping may effect some more than others.
For example, of the three listed I would use a light mist of Waterless Wash if the car is still realitively wet.
If the paint is fairly dry (hit with air blower or wiped with a damp rag) I would go with Midnight Sun Instant Detailer (or Waterless Wash).
If there is very little standing water on the paint then I would use Polymer Spray (or any of the other two).
When you say you are going to use this as a drying aid after a rinseless wash, I am assuming (please correct me if I am wrong) then you washing the section then drying most of the standing water first, then coming back with a second towel (and using the drying aid during the final wipe?).
If the above is the case then any will work fine. If you are using a carnauba wax as your LSP, go with Midnight Sun and if you are going with a sealant, stick with Wet Diamond Polymer Spray. (You could also use Midnight Sun Instant Carnauba Detailer on top of a sealant for a deeper, more carnauba like glow).
