Does Djay Pro allow to assign different libraries to each channel? (iTunes to Channel X, Spotify to Channel Y)

I’m thinking of grabbing the Pioneer DDJ-SX2.

My main issue is that I currently (with my Mixdeck Quad) utilize a USB stick (split channels), turntables and …Spotify via the iPad.

I cannot find another controller like it, but need to upgrade.

With the SX2, I can use Serato …or…Djay Pro – but to my knowledge, not both at the same time (so therefore, no mp3s WITH streaming - just one or the other).

Then I was thinking, is it possible for Djay Pro to split libraries by channel? In other words, assign iTunes to Ch X and Spotify to Channel Y.

Unlikely, I would imagine. But I’m curious.

Conversely, it sounds like upgrading to the Pioneer SZ2 (with dual USB ports) allows for one laptop to connect to Serato, and the other to Djay Pro.

Kind of an expensive (+$1000) upgrade just so I can play Spotify, I realize.

For context, I’m not a club DJ – I’m making some bedroom mixes, trying to advance to video soon, and also “trying out” a lot of new music frequently (which is why I would prefer not to spend hundreds a week on downloading).

Thanks for any feedback!