I have used a no brand wire feed. They are not the greatest. But if you learn to weld with that, then when you get your hands on a good welder you will feel like a pro.
The biggest factor I have found on the 110V low buck welders is to run no extension cord and plug them into a good wall outlet. The voltage drop on an extension cord will make the welder pratically unusable. Same goes for a poor outlet. Plug a normal light bulb into the same outlet as the welder, if it goes very dim when trying to weld, there is too much voltage drop at that outlet.
Flux core is usable wire. Not the most desirable for pretty things, but has it's place. I recently burned a spool up doing horse corrals, ropping boxes and shades at the uncles house. didn't need to be the prettiest and welds better when outside (shielding gas doesn't blow away in the breeze)
Another thing, make sure that you are trying to weld steel to steel. That welder won't weld aluminium.