Like Nick4u_81 my opinion is also biased but for the Marantz - both receivers will likely be to your liking. The Onkyo I believe has the ablility to process the new lossless codecs while the Marantz does not - but if you are like me and the decoding is done at the source (PS3) then you're all set. However if you ever wish to add an amp in the future then the Marantz has the 7.1 pre-outs required while the Onkyo only has the sub out according to the specs.
Again just an opinion +1 Marantz
