why are the "direct replacement" cat converters so expensive? like $250 vs. $80. are they better? are the $80 ones restrictive or something?

im looking at redoing my exhaust since the PO decided it was a good idea to run it under the crossmember. as in the lowest point under the truck

 

It's a matter of supply and demand. A universal fit converter is typically cheaper because it fits more vehicles therefore a wider market appeal. A direct replacement converter usually includes the pipes to mount it in the factory location.

A universal converter is just that: converter only, some assembly required (no batteries included!)