What are you welding with?

Just get a wire feeder for those machines you already have. Unless they are not AC for aluminium
It boils down to what your wanting to accomplish and what you want to spend
Those Everest machines look interesting and are cheap enough. A buddy just bought one and says he is satisfied, however I wouldn't want one for commercial work, in that case id go with Lincoln or Miller.
Even the inverter Lincolns or Millers are expensive to fix, the cheap machines would be throw aways