A few videos on Youtube with multiple failure to feeds was enough for me to stay away from both. I also recall a thread on here of a RM380 owner who mentioned a pin that worked loose a little.
So far, my RM380 has eaten all ammo I've put in it, but it's only had a few hundred rounds put in it to date. So, long term testing is far from over.
Regarding the takedown pin, it is trapped by the slide and nothing else. The trick to keeping it in place is to know the gun. Knowing the gun means, use grease on the pin and cam slot and also don't slow rack the slide. Rack the slide briskly and shoot the gun.
When I first got my RM380, I bought it at the same range I was trying it out at. It was lightly lubed from the factory (Rem Oil?) and I didn't read the instructions before testing. The gun ran great for me, but I handed it over to a novice shooter friend who jammed it right up by pulling the slide slowly.
Once I figured the pin had walked into the takedown hole (due to the slow slide handling and light lube), I showed my friend to not fear racking the slide briskly. He took the advice and there were no other problems then or since.
(That same novice shooter friend of mine also caused a double feed jam in my SKS several weeks prior, of which that SKS has never had a feed problem before. I think he is all squared away on running semi-auto slides and bolts now.
)
The aforementioned dab of grease helps if someone does rack the slide slowly. The problem with gun counter checkouts of this gun is, the gun is lightly lubed and people rack the slide with the usual gun counter caution.
The bottom line is, I'm not trying to sell someone on the takedown pin design on the RM380 or the Rorhbaugh. I'm just trying to say that with proper knowledge of operation of the RM380, that the gun works and it works well.