I'm pretty much a novice wanting to purchase the Mordaunt-Short Avant 900 package, and I'm very confused. On the richersounds website the Avant package is mentioned as being THX, though on the MS website the Avant 900's aren't mentioned as THX anywhere, only the 500 range is. Forgive me if I have missed anything and am speaking utter nonsense, it would be the first time. Also, what is the difference between the 500s and 900s? Which is best? I'm not overly fussed about amazing music as would prefer better quality H/C.Sorry again if this has been touched on in an old thread that I haven't spotted. Also, I was planning on running them off an AX5i- any comments, Thanks. Oh yeah, and would Richersounds be the best port of call?