Looked at both yesterday.
No comparison.
HF was a much better box, IMO.
Much heavier, tighter slides, drawers had less play when extended.
The SS box screams "Costco Special, I got a hot dog and a soda with it for for $1.50"
I also looked at the 56" HF- I believe the 44" is built heavier. Just my opinion, YMMV
But man what a hot dog & soda for $1.50! My wife hates when I go to Costco because I'm always burping up the hotdog for the rest of the day...
About 100 guys at work have the US General boxes from HF. None of them have had any complaints 44", 56", and 72".

They have 4 different boxes in the 41-42in range, Trinity, Excel, Stanley & Kirkland:The Costco seems pretty nice too, but I think the layout kills it for most mechanics.