All of us at CrunchGear can testify that Logitech makes solid audio gear. The Z623s are a good deal, the G35 headset is a monster, and Greg says he’s been using the Z5500 5.1 system happily for several years now. Well, Logitech’s new Z906 is meant to replace that last one: it’s a brand-new 500-watt 5.1 system selling for the totally reasonable price of $350 not quite as…