About the two types of RV antifreeze:
J&M CamperFraserway RVCamco has both types of antifreeze. Buyers tend to buy products based on price which is why the big box stores and RV vendors sell the cheaper alcohol based stuff. Try an independent RV repair/parts/accessories shop which is where I bought our Camco PG antifreeze. I blow our lines out and use antifreeze in the P-traps and toilet bowl and one jug of it lasts a long time.
Watched an episode of Forensic Files recently and some lady killed her husband with antifreeze. Cops found a suicide note with the words "antifree" and then when in an interview she said "antifree", they new they had the killer. Moral of story - if you want to do someone in, don't use PG RV antifreeze and make sure you know how to spell... :R