[popcornmix]

Now my question I just want quick clarification on the DTS-MA/TrueHD decoding. I personally have a 5.1 setup, however it sounds like if I disable passthrough and set my speaker configuration at 7.1 I should get PCM for DTS-MA/TrueHD correct? This group is amazing and definitely is helping sales of the Pi2

Yes. If you select 7.1 for number of channels then Kodi will not downmix the audio, and the receiver should downmix to 5.1 (as long as it has been set to 5.1 or can autodetect the speakers connected).
If you select 5.1 you will still get the lossless audio, but Kodi will downmix to 5.1.
If you have passthrough enabled then the receiver will decode the lossy DTS track.

Try all 3 options and see which you prefer.
I imagine to tell the difference between the lossy and lossless audio you will need good ears and a good sound system. There shouldn't be a lot of difference.
Obviously if you do have a 7.1 system then the difference will be more noticeable (a whole extra two channels of audio).