Are Bang and Olufsen turntables any good?

They are excellent turntables. With proper care and maintenance they will last a lifetime. I bought a B&O 4002 turntable, new, in 1978 and it performs like new. They need periodic servicing performed by an expert technician. They have a very sophisticated and unique pendulum suspension that isolates the platter and tone arm more effectively than conventional designs. The tangential tracking versions are marvels of engineering excellence and design. The B&O moving cross phonograph cartridges it uses have lower mass than MM or MC designs. For best results it needs a high quality phonograph amplifier.

It has problems with bass. It is kind of a lightweight. If you have it now, don't fear for your records, it will not harm them. It just won't be terrific. If you are a bass-head then dump it and try others.

NO not really!!

If they are light in the bass, I remember their "state of the art" speakers were heavy in the bass....good combination.

Dpaulku, If the seller told you that the (diamond) tip of the MMC5 "oxidized away" in his closet, he was selling you a bill of goods. That's pure hogwash. The MMC5 is not as good as what you have now, the MMC2, but diamond is diamond. It's as stable in air as any material on this planet.