I have the yeswelder mig 250 pro with a tank of c25 argon/co2.
I have been working on a jeep wrangler (jk) and i needed to gusset the front c's, sleeved the front axle, and a truss.
I also used it to make my own step/"slider" mounts for a set i picked up for $50 among many other things.
As a complete novice, i have been making good use of it.
The biggest thing i noticed was the ground lead didn't lay on the ground right.
Felt stiff and too light.
Turned out to be copper clad aluminum.
I had some weird inconsistencies when using it for a longish times in one go.
So i replaced that with a pure copper lead in a "feel the force" moment.
That made the biggest single improvement on the thing.
The other big upgrade was after i burned my only .035 tip and the gas cup on Christmas eve.
I took a chance at my local tractor supply and picked up a set of hobart tips and gas cup, hobart makes a metric set.
I just eyeballed the threads and bam perfect fit.
Much higher quality, thicker too!
The final big upgrade was when i bought a new ground clamp.
The yeswelder one pretty light duty.
There are also some copper clad leads inside the machine, goes from the board to the lead quick disconnects.
I changed those, i didn't notice a huge improvement but it's done.
That welder has been doing great for my use so far, I'm happy with it.
I did some sheet metal work that turned out "ok", but that machine isn't rated for anything thinner than 16ga, it was pretty difficult on the 22ga i needed to patch.
It's also supposed to be capable of lift-tig.
I bought the attachment, but then i found out it won't work with a foot pedal switch.
One day when i have a solid need I'll try their dedicated tig.
I have been thinking about a light duty mig for sheet metal, but that's not a huge priority right now.
For the money, the 250 pro is a good machine for my use...