Krell/BMW model designations?

Has anyone noticed that Krell and BMW designate their products very similarly? Krell has the 400xi, BMW has the 330xi, etc. Just a stupid little observation :)
I think the owner of Krell is a BWM fan. I read somewhere that he owns a M5.
Is an M5 just like the M3, but only in the 5 series?
The M version of a BMW is always the high-performance version of that same series (M3, M5, M6). The M3 is a 3 series with upgraded suspension, engine, brakes, transmission, etc.

The M5 (2000-2003) has a 400 hp V8 engine and does 0-60 in about 4.7 seconds. That's Ferrari fast! Not bad for a 4 door luxury sedan!

(BMW fanatic)
Dan D'Agostino is into Audi and Porsche products (he currently has a Porsche Cayenne). I don't believe the model designations have anything to do with BMW. The FPB amplifiers became "X" series almost two years ago. The change from the 300il integrated amp to the newer 400xi may be that the changes are similar to the changes that occured with the FPB series. I live about 40 minutes from the Krell factory, and have visited the facility on numerous occasions, and have seen Dan with both Audi and Porsche vehicles. Even if there were any relationships between model designations (BMW/Krell), it would be an intelligent marketing tactic. Let's face it, most people I know that own the higher end Krell gear usually drive Benz's and BMW's, and sport Rolex watches.