I myself have only used the rinseless once and have not used waterless at all. From what I see to me the rinseless would be safer, I say this because you use a 2 bucket method in rinseless. I pre-soaked the paint with a spray bottle of solution like you would with the waterless (fine mist layer doesn't bead as easy as a layer of water does). You soak the MF towel or mitt, in my case I used a towel and not my wash mitt, in the solution and then wash your pre-soaked section. I actually wiped in a straight line and turned the towel in a upward fashion as I was moving across the paint, flip towel and did a pass along side this. Now you rinse your towel in the 2nd bucket to get the dirt particles out, ring out and return to solution bucket, dry section and repeat on next section.
I have not used waterless and think it would work fine for light dust but in my case the car is a lot dirtier and this is where rinseless I think works best. I have to be extra careful because of the salt used here in MN but by rolling the towel upward while moving across I think helps pull the dirt off so it remains in the towel.
I am actually headed out to the garage to do a rinseless wash this morning. I had to take it to the car wash first because it was a little wet the other day here and it really got a lot of road grime and salt on it. The quick wash and rinse I did was enough to get the major grime and crud off but there is still a layer on the car making it look dull. Just my noob opinion but hope this helps.
Dean. :bigups