I have used a Beomaster 8000 and Beovox Pentas as my main system for four years now, and as Peter says, I am extremely happy with it. I used to own a Beomaster 5000 and did try running the Pentas with it, but I was not very impressed compared with the 8000. I also have a Beomaster and Beolab 5000 system that has recently been serviced, and I think the 8000 shades this too in terms of performance. It is probably worth pointing out that if your friend's 8000 has not been serviced, then it is probably in need of one to get maximum performance and reliability from what is a complex and powerful bit of kit!
Looks and performance-wise though, you can't go far wrong with this set up :)
President, Beomaster 8000 Appreciation Society