Yeah RM are shit. The situation again, which is why I prefer Amazon these days is:
RM -> drop at doorstep, does a runner, gets nicked by porch pirates, cause argument between seller and yourself over what "signed for means" after it gets nicked and who is responsible (seller says signed for and not me. You say I didn't sign for it). Either that or red slip, chase the fucker up the street and find he didn't even have the package with him.
Amazon -> drop at doorstep, does a runner, gets nicked by porch pirates, amazon refunds / redelivers no questions asked.
A couple of years ago we had a postman who was clearly a fucking idiot because he delivered stuff regularly to the correct house number but on the wrong street. The other address was pretty dishonest and just pocketed the stuff and denied it.