The standard release of Personal Stock Monitor costs a bit more than its closest competitor, WinStock ($29.95 compared to $20), and lacks a few important features like WinStock's enhanced browsing capabilities and automatic foreign currency conversion.
Overall, though, PSM is a great stock ticker client that packs a lot of power into an inexpensive package. And if you find that your needs demand a bit more power than the standard release offers, the Gold release will surely satisfy.