Neither schematic shows the most expensive components: the transformer
and filter caps.
If you have a 24VAC transformer and a full-wave rectifier you have
something like 31 or 32VDC under full load. That's not a lot of
headroom if you have brownouts etc to worry about.
It also seems that neither has any overcurrent/crowbar protection. If
your pass transistor fails shorted and everything still works and
nothing blows up... maybe you didn't need a regulator in the first
place :-).
Tim.
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