[kragen]

Oh! I usually think of availability as an advantage for 74HC (maybe not 74HCT) over 74LS, but maybe that's not the case where you are. Local availability is a real advantage.

The electronics parts stores in my town (Morón), which are several blocks from my house, have a fairly limited part selection, mostly for repair purposes. So part availability is a very significant concern. I was shocked to find last month that one of them didn't even have a TL431! But another one on the same block did.

I thought I'd check Digi-Key, but it seems like 74AS244 is even more than US$4 there in onesies: https://www.digikey.com/en/products/detail/texas-instruments.... However, a CMOS 74AHC244 (nominally something like 5.5ns to the AS244's 6.2ns) is only 27¢: https://www.digikey.com/en/products/detail/texas-instruments...

At Digi-Key, the CMOS parts have better availability in this case, but that says nothing about the availability at the corner store.

Thank you for explaining!