I assumed they would all be the same, only one style was fixed and required less
componets...

I have 5v regulators that barely manage .5A, 12v ones that give me 1A, and the
317 that is reliably 1.5A, sometimes as high as 2.2A.

Additionally, the voltage regulation is much tighter with the LM317.

I know we're all moving on to switch-mode, but I would have thought the linear
options would have been well sorted out by this date.

 

Can you give a circuit? The datasheet says more than "1.5A" for LM317 and up to "1.5A" for LM7805?

 

The current capability depends a lot on the package used.
Just remember, the 78xx series regulators are very old. There are much better regs around now, but do you really need them in your application?
78xx regs are cheap and are available "everywhere".
And I imagine various manufacturers have their own versions so that comes into the story.
Read the data sheets for the particular make and model if you need closer info.

 

Hello,

If you want some more modern regulators, you could have a look at the LT1083 - LT1086 regulators.



See the attached datasheets for more info.

Bertus