I have a 48SX on my desk that I use almost every day. It's not just the notation and interaction that is nice as there are plenty of calculator apps that suppor

I have a 48SX on my desk that I use almost every day. It's not just the notation and interaction that is nice as there are plenty of calculator apps that support RPN. The tactile feel of the keys gives good positive feedback that you haven't missed a digit when calculating in a hurry.