Today, the thing that makes the HP48 series much less useful is simply that they lack a backlight.

I find them simply difficult to read and use today because of that.

So, I just use a HP48 app on my phone. It's not as good, lacking the tactile response of the keyboard. But it's close.

I used to program the 48's. You think laptops are convenient, wait until you try coding in bed on a 48. Very comfortable, if you can stay awake :).