FLX 10 or All in 1 device ?

Hi everyone ! Producer and aspiring DJ here ! I've recently got a lot of free time this summer that led me into the amazing dj world, starting with an FLX 4 and rekordbox.

Through days of daily practice, I've realized that I would be able to do more and efficiently what I want with a 4 channel deck (and stems).

However, I'm wondering if the FLX10 is worth upgrading to (having a computer isnt a problem), or if I should invest in an all in one deck (like the xdj series) or a completly different brand / model.

Your advices would be precious in my decision !