The Record frame was better than most of the comparable Euro-stuff in it's day (unfortunately, Japanese Bikes still lacked initially any cachet, then). The Sprites tended to be Nottingham made (like the three speeds 'Sports'. etc.) Records came in variuos versions- some Nottingham made, others Carlton made, still others Gazelle or Irish made. But all are respectable (though I prefer the Carlton-mades, personally). They did have Raliegh proprietarty headsets but depending on year or source, they might not have Proprietary threading in the bottom brackets- some even had Stronglight Steel cottered cranks.
As for rear derailleurs, I think that the Simplex shifted better than the Huret Alvit, but the Alvit was much more durable and reliable- you could even repack the loose bearings in their pulleys! The Simplex FD was more fragile than the Huret one as well. Back in the day, one immediately changed the RD to Suntour for reliable ,fast shifting. The $8- $12 VG or VGT models were ideal. The crummiest part of the Simplex gear system was , hands down, the plastic downtube (or stem mounted version) shifters. They were finicky and could be snapped in cold weather. These were usually the second item replaced on the bikes! I built a nine speed commuter (Sturmey Archer IH 3sp. w/ Cyclo-Benelux triple cog) using a red Record frame, back in the early eighties. The bike was bullet proof and stable . Sadly, it was stolen in PhHiladelphia.
In short, $10 for a record is a steal!