Digital out... does source matter?

Ok... Maybe I'm going to get some heat for this but here we go. I want to get a nice CDP. I'm currntly running the av multi out of my ps3 to my amp. Honestly, it doesn't sound bad. I think it rather sounds pretty good. I'm going to get a DAC for the sake of the Sonos player so I'm considering running optical out to the dac from the ps3. Here's the question. Would I really even benefit in buying a CDP if i ran with this idea? The dac would essentially be the sound. Isn't digital just that? Digital? I have a few cdps on my list ranging up to $1500 or so used and new. For that price should I just invest in a really spectacular dac and call it quits? I feel like without a cdp I'm seriously missing out on something in a sonic manner and, yes, materialistic manner. I'd still like a cdp but if I wont get much of a benefit in the price range stated above then I guess I just need to hold out a bit longer. I'm still considering the McIntosh MCD201. Of course I've only listened to it on a reference system. Not my GS10s. And it is in my price range. I am looking for resolution to balance out the warmer side down the line.

I know this post is a little scattered but if you can make sense of what I'm asking I would appreciate all insightful replies.