I was under the impression that the HP42S and HP17Bii were the same appart from the case printing, internal ROM and some other minor differences. Also I think the HP42S service units (replacement units for broken ones) were made on the same production lines as the HP17Bii until very recently (2000?).
I notice that HP don't seem to offer 5 year 'end of life' support for their products (was the HP42S the last one for this).
However not wanting to knock HP too much I am not supprised that the HP42S was stopped and all pleas for it's return are rejected. In the current market people always look at the bang per buck. Teaching them that the HP42S is as near as perfect a calculator as has ever been made (OK '41 had much better input/output) is futile when you can lure them with bigger screens, memory and massive feature lists.
Remember HP are there to make money for their share holders and since Mr P and Mr H have gone to that engineering lab in the sky any pretense of other values can be taken with a large pinch of salt. I had my fingers burnt with the HP49G's joke of a manual and will not buy new HP products until they are supported properly. (Mind you they have got my $ from selling the HP49G so why should they care to support it as support just cost money they could spend on advertising).
Anyway enough of my ranting...