Oh of course I know that DTS sounds better than the top tier 640kb/s DD 5.1 stuff, but sometimes you don't have a 'choice' HEHE.
With regards to file sizes and such; video quality wise, all else being equal, then the 448kb/s DD 5.1 version would look nicer than a DTS 1.5mbs/s version. Of course if the video quality is acceptable, then I will agree that the DTS version is preferable on the whole.
The majority of my files are DTS 1.5 or DTS MA anyway. I don't have the greatest sound system (SVS 5.1 set).
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But it's good enough to allow me to discern the difference between AC3 640 vs DTS 1.5, vs DTS MA / PCM / True HD etc.
So yes of course, better audio is preferred, but sometimes, you are stuck with AC3, I just disagree that the overall quality suffers much, in fact it's technically possible for the video portion to be better as I've mentioned before. It's not a worthy trade off in my opinion, but rips using AC3 aren't automatically "bad".