Which calculator would you give as a gift? That depends on the person it is destined to. Let’s see a number of cases:
An engineering professional: most of the engineering professionals I know don’t use a calculator anymore! But those who do, are in two camps: the elder, who use scientific calculators (as may be the HP41 or HP52, or even 15c), and the younger, who use a calculator of the HP48 family (which for the sake of the argument include the HP50g and HP49g too).Most got stuck with one of the original 48s, sx or g - and have never considered to change. These calculators were built like a tank, and they will never fail on their own - so there is no need for a new calculator for them - even a better one (but that he will not appreciate so much)
But I have found many that had one of these calculator, and lost it (or most likely it was stolen from them), and they would really want to get it back. if you can find a used 48, that’s the right gift for them; but they can also have a new 50g and enjoy the difference in speed and the much better display and feature set. Also the possibility of communicating with their computer, backing up their calculator and load programs from the internet - all of these things that he can’t do with a 48 (lest he still has a serial connector in his computer!)
A financial professional. If old, he probably had at moment of his career a HP12c - if he’s lost it, please give it back to him! He doesn’t need any more features - that’s the perfect financial calculator for him!
If young, it may be that he has not been exposed to HP calculators. Then the clear gift is the HP17bII+ (if you’re confident with him, you might give him a used 17bII - it is as good and with better key feel)If you’re not so confident with him, a HP10bII is an excellent tool that looks the part. Avoid at all prices the HP30b or (god forbids) the hideous HP20b. Excellent firmware in a shitty, ugly body!.
(Tomorrow we will continue with other cases - in particular the different cases of students of different ages and levels)