Some time ago an ex-employee of ACO said when thay closed them down that:
"Unfortunately, the Saturn is becoming obsolete this year, and nothing has been done to redisgn it"
All the current (and recent ex) RPN calcs had the operating system running on a Saturn processor. It doesn't take much imagination to see that when stocks run out HP will have nothing to run the RPN software on.
Hence HP is re-badging old calcs, or using AOS based chip sets.
The only chance to use all the good RPN routines is to hire some programmers to port it to another processor, or have an interpretor running on a faster processor (both difficult as the Saturn is a fairly unique bit of hardware)
The only other (minimal cost) option is to use the 11/15c roms in the 'new' 12c - you know, the one with the rubbish keyboard.
Other choices are to desing a new calc (remember the Xpander?) or have a good RPN calc on a PDA or using the 48/49..... but the chances of HP doing this are 1 in 10^42.
Buy those hp48's while you can...
(well thats my rant for this month)