Let me know how you like that miller table, I am looking at one.
I haven't actually used it yet for welding (its been over 90* out daily since it was delivered) but I have some initial impressions:
Its heavy. I mean, I knew it would be heavy, but it's HEAVY--75 pounds. It has two small wheels on it to roll it like a wheelbarrow when its folded up. They are helpful, but you'll be lifting it over any decent sized obstacles.
Made in China. Not happy about it, but...meh. It was extremely well packaged. Zero damage in shipping. Cyberweld.com has been fantastic to deal with.
The clamps do cause very slight deflection of the 3/16" top with moderate clamping perpendicular to the slots.
It has plastic feet on the bottom of the legs. They were more chewed up than I liked to see after simply setting it up and folding it to store. In their defense, our concrete is like sandpaper.
Its very solid, stable, and sturdy. I'm 235 lbs and it didn't flinch when I hopped up on it--it's rated for 500lbs. It's tall, probably about 36". Comfortable position for tall people.
Its a compromise to make it portable. A thicker top would flex less, but would make it too heavy and awkward to set up. For my purposes, I see it lasting a lifetime. It takes up virtually no space when folded, and that's what I need right now.