To add, both devices use JMRI to do the programming, which is free software. If you don;t currently have anything, and don't plan to use Digitrax sound decoders, the SPROG is the best bet, it programs and reads significantly faster, plus can actually run trains, sort of a poor man's command station/booster.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If all you want to do is program decoders, get a Digitrax PR3 and use it in it's stand-alone programming mode. No Digitrax (or other) command station is needed to use it in that manner.
If you also want to test-run locos after you've programmed them, get a SPROG II.
I'm in the market for a very basic DCC system. I'm in a modular club, so I don't really need anything that can do heavy lifting. All I really need is the ability to reprogram my addresses and other minor tasks at the workbench I tried my hand at that new fangled DCC++, but apparently its beyond my skillset to get the dang thing working. What's out there at the lower end of features?