I launched a 5,000-digit computation, with a program which I'm almost sure isn't the best one in terms of speed. I found it here* :
http://serge.mehl.free.fr/anx/pi1000_basic.html (computation of digits of e is on the same site)
and translated it for my RPN machine. It will run for approximately 80 hours. My machine's average execution rate is around 2,000 RPN instructions per second, when using only simple arithmetic. The longest computation I could launch is 13,930 digits, for an estimated duration of 28 days. (already did a successful 16-day computation of 15,928 digits of e)
I had noticed the thread you mention, I archived the documents for a later study
*last year I ran the e computation on EhBASIC, when my calculator firmware still didn't exist : 30,000 digits in 2 months (1-MHz clock rate, compared to the current 6-MHz one).