I think it is very much so worth getting. Just download it and use it for a bit to see if you personally like it, then purchase it. You can't save or print until you buy the full version, but the utility should present itself before you make your decision.
^_^ And there's a very helpful community if you're wondering how to do something in there. Heck, I've written a number of extensions for it when people want to do something specialized that involves changing rules.
It supports a number of game systems, although you have to pay for the license for each one separately. Not that you need to purchase all of them, of course, just the ones you want to play.
I personally LOVE haveing Hero Lab to slam out characters really fast. It's especially useful for GMs, although dedicated players (or those who play online via Skype or whatever) might find it well worth the price.