Some good advice above. I have always sent RIF's over the past 15 years odd PF 24 and never had an issue - and I never take it to the post office and instead get it collected. I have also had them sent to me that way just fine too.
Enhanced compensation isn't available if you send it 48h or 24h anyway so you are at the mercy of the system regardless and my thinking is "if its going to go wrong, I'd rather it go wrong fast" when it comes to posting things, so that I can react to the issue just as fast. Luckily I think PF have gotten a lot better over the years, especially iow they are more under Royal Mail. I had an issue sending a guitar once but they fixed it quick. Also, even if you do lose something that is covered, I believe they would make it very hard to claim anyway.
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