The BSR 810 and 710 are of significantly higher quality than other BSRs. BSR was the largest turntable maker in the world, but it didn't get much respect since their products were aimed at the lower end of the market. With the 810 and 710, they decided to try to compete with Dual and Miracord. The turntables were potentially at a comparable level, but BSR used a completely novel cam driven mechanism with them, and there were teething pains with production, and then pretty complete disaster when people tried to have their turntables repaired, and the repair people didn't know how to fix them (and hated them). Given that they came out about the same time that the Japanese belt drive manual turntable tsunami (led by the Pioneer PL 12d) hit and changers suddenly became out of fashion, the turntables were a flop.
If you can find one that works, they are actually very nice. I have one that I actually got to work, all except the arm lock, which I cannot figure out. I need to replace the motor mounts - they had sagged, and unevenly, but even so it sounds good.