Which is better for a garage or shop ceiling?

The Ouyessir, because it is listed for commercial use and has the stronger owner rating. The Deiokin is described for home use only.

Do they fit the same rough opening?

Yes. Both need a 22.5" x 54" rough opening and fit ceilings from 7'8" to 10'3", so either drops into the same framed hole.

Which one lasts longer?

The Deiokin is all aluminum, which resists wear better than the Ouyessir's ABS parts over decades. The Ouyessir has better owner feedback, so its real-world durability looks solid too.

Is the Ouyessir worth stepping up to?

Yes for most buyers. You get the same capacity and fit with a higher rating and more reviews, and the ABS parts add stiffness without changing the install.

Can one person install either ladder?

Both are heavy folding units, so plan on two people to lift and seat the ladder in the opening. The Deiokin ships with detailed installation instructions.

Deiokin Aluminum Attic Ladder vs Ouyessir Aluminum Attic Ladder

Both are 22.5" x 54" aluminum attic ladders rated for 375 lbs and ceilings from 7'8" to 10'3", so the fit and load numbers are the same. The Ouyessir is the safer pick: it has a stronger owner rating (4.5 from 25 ratings versus 3.5 from 11) and adds ABS parts to the aluminum frame. The Deiokin is the plainer build with a smaller review base, so there is less owner feedback to judge it by. Buy the Ouyessir unless you specifically want an all-aluminum ladder.

Choose the Deiokin if you want a straightforward all-aluminum ladder and the smaller review count does not bother you.
Choose the Ouyessir if you want the better-rated ladder with more owner feedback behind it.

Prices

Deiokin Aluminum Attic Ladder: $259.99 at Walmart (last seen Nov 10)
Ouyessir Aluminum Attic Ladder: $259.99 at Walmart (last seen Nov 10)
Difference: both cost the same at the latest prices (Nov 10)