Patrick over at Developing for Dynamics has a great solution for those of you using Dynamics GP 10 and beyond.
I tested this out on my stinky old PC. I downloaded 20,000 rows in about 50 seconds after making the dex.ini switch. Without the switch I quite after a 1 min and 15 seconds and had only downloaded 2000 rows. Extrapolated that would have taken 12.5 mins to do 20,000.
This has been a limiting aspect of smartlist in the past so was pretty syched to see this solution.
What a great find.