When we bought our house one bath was hooked up with PEX. Something didn't look right about the connections. Sure enough after we installed the toilet the tank filled up with hot water. I didn't have the crimp tool to fix it but the double O ring compression connectors made for it worked great to fix it.
The RV/marine hoses work fine and I use campden tablets for the chloramines. Everything gets boiled in the end so no contamination problems. We did have a RV hose explode in the Florida sun once. Fortunately a neighbor saw it and shut it off.