Ok, I am entering the world of HiFi and have read pros anc cons about all in ones. I need a system that would go in the bedroom and potentially wake me up with an alarm. Decided on the Denon M37 and then went and had a look at it in John Lewis.....ok whats with all the holes? I guess its to cool the system but what an ugly thing on top. So why are some micro units enclosed and others not?