I honestly don’t know why anyone would but metal flats anymore as composites are cheaper, lighter, look better as they age, just as grippy (maybe better grip).
Cheaper, lighter & scrap once you clout them into a rock & deform them along with ripping pins out which you can’t replace as the hole is twice the size.
Also, absolutely not ‘better grip’ than a decent flat pedal. My OneUps are demoted to the pub bike, they are that bad.
As to what to buy, for that budget a secondhand set of Deity T-Mac, Stamp 11s or Horizon DH if you want some actual grip.