Looking at all of the kits available is confusing. Why does a $300 GR research kit have a similar frequency response plot to say a $600 Ellis audio 1801 kit or a $1500 Madisound thor kit or even the GR res. line array kit. Does this mean they sound similar even though there is a huge price diff. I'm confused by this not being able to listen to any of them and compare with my ears. Also, if I'm only planning on using say an Onkyo SR600 or Dennon 2802 to power my speaks, does it matter if I spend the extra money on the 1801's?