I just picked up a Beogram 4002.  I hate to say that I feel like I got ripped off.  I have to admit that the unit is pretty much perfect cosmetically, and has a like new MMC 20S.  Please don't let me know that I paid too much.  I just thought it was super cool so I forked over $400.  Like I said, please don't rub this in since I couldn't resist.

I came here for some help with the setup.  This is my first nice record player, so I didn't realize I needed a phono preamp.  After already spending too much on the deck, I headed over to Amazon and bought an ART phono preamp for $40.  

How do I setup the ground wire?  

Also, the owner said I needed an LP mat to make the stylus last for a long time.  Is this right?  Any mat that you would recommend? Or does it not matter?

How will the sound of this unit compared to my crappy Ion Turntable I picked up from Urban Outfitters (see pic below)?

Welcome! I don't think you were ripped off. Externally good units always get a lot more expensive. The cartridge is the most basic model, but that can be replaced any time if you wish.

Do you still have the correct 5-pin DIN connector on the deck, or has it already been bastardized to RCAs as everybody in the States seems to do?

Forget about the mat. It won't improve anything and will prevent the record detection from working (i.e the deck will happily lower the stylus on the mat!).

And yes, it will show your Ion the door if the cartridge is OK

Thanks for the reply.  It still has the 5-pin DIN connector.  Good to know I wasn't completely ripped off...  

What about that ground wire?  

You'll need to connect the ground of the preamp to the metal sleeve of the DIN connector.

I assume your preamp has RCA connectors, so you will need some kind of an adapter. There exist some for this particular purpose and they have the grouding connection included, but a separate wire will do fine as well.