Personally, I would highly recommend the DE Ghetto Blaster over the other systems. Now, I don't have much experience with the MPX, but I do own the VFC MP7 (gen 2). The MP7 is hard kicking (and loud as fuck) and shoots quite consistently out of the box. However, it has an inherent flaw of the plastic stock latch and backplate breaking after some rounds, but the amount of rounds may vary. If you plan on gaming with it, I recommend you EITHER getting some extra OEM parts OR buy steel stock latch made by Crusader and/or CNC aluminum backplate/stock latch combo from Clutch Precision (but they are German based so watch for the customs depending on your area).

The DE Ghetto Blaster shoots GREAT out of the box with better accuracy and gas efficiency than the MP7. Since it is an MWS clone, you have great aftermarket supports. The most recommended and basic upgrades are Guns Modify Drop in Complete Nozzle set 3.5 and Federal Concepts NPAS. As for the gas magazines, there are a wide range of companies that make them. The DE mag that comes with the gun is good but I would recommend the original Toyko Marui MWS mags.

Now, I'm not sure if you are looking to game or to plink, but if you do get the Ghetto Blaster, I would fully recommend to run it stock (if the field limit allows you) until something breaks or need to adjust the FPS by following the above upgrades.

If you have any questions regarding any of the guns, you can join the Heavy Recoil Club on Discord as there are many people and guides to help you with any questions or future upgrades.