Reply to S4 and TSP2

I own a Kontrol S4 running TP2 on a MacBookPro 2.4 GHz Intel Core i5 4GB MacOSX 10.6.7.

I am considering upgrading to TSP2 to use timecode control with CDJs or turntables.

Here are my questions/concerns:

1. Would I be able to switch on the fly between timecode and straight up S4, basically turning timecode off, so to speak? And would the S4 keep full functionality of all its sections when upgrading to TSP2 and not using the timecode control?

2. Would I be able to switch on the fly from the timecode function and use CDJs or turntables to play CDs/vinyls, basically using the S4 as a mixer and the CDJs or turntables as external hardware setting up 2 decks for that purpose? There might be a different path to allow this function and, if so, does anybody know how to do so?

3. Does anybody have any experience with such a set up and could tell me if I should just stick with just the S4 or consider any different gear for that purpose.

4. Finally any 2cents in practicality and sound quality with aforementioned setups.

Thank you all so much ! ! !