First: Love the enthusiasm but you posted in the wrong forum section.
Secondly: DJ Vintage (Who is a forum mod on here) has basically answered so many of these that he’s boiled it down to a list that should help you quite a bit.
Here it is: “1) Determine workflow
2) Determine software choice
3) Determine budget
4) Pick 2 (max. 3) controllers that fit workflow, software and budget
5) Get some hands on time if possible
6) Make your choice”
Hopefully this helps as it sounds like you need a good starting point before just spending money on a controller. Otherwise, you’ll end up frustrated & end up giving up without making any sort of progress.
To answer your post, 1.) Almost all intro controllers now use the same sound-card now-a-days, so basically you’re just paying for the features & name. The MTP3 is a great start no matter what as it is a great all arounder to dip your toes in the water and see if you want to really do it. (I own the OG MTP and will keep that baby forever)
The SB2 would be good as well and teach you things the MTP3 can’t, like gain staging your tunes.
The universal, I don’t know. It strikes me as the kind of thing you would buy if you want to DJ using your phone/tablet first. I’m not a fan of them taking away a physical headphone volume knob and going with a button system, as that can be hit or miss. One click up, it’s too loud. One click down and it’s not loud enough unless it’s in super small increments.
2.) All the ones you listed are power & midi over USB. Which basically means they need to be connected to something like a computer (unless the universal does mains power) in order to work. If you’re asking if you can plug in a USB stick and go, then no. I do know a a few things that do that, but they might be out of your budget.
Best of luck!
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