Not time-limited, no nag screens. Good basic sounds, especially for a free instrument.
It's a player and comes with a very useable acoustic drum kit. There's a variety of presets, which all have an info panel to suggest the genre of music they're best suited to. There are enough options to let you fine tune each kit element and save your tweaked kits as new presets.
Like most drum VSTs you have a library of groove patterns, I'd say these are mainly useable and not too busy.
You can purchase additional drum kits and grooves. (I suppose the point of player software is to get you to buy in to their eco-system). Once you have more than just a single kit you're able to mix-and-match elements, swapping the snare drum for example. I already had Addictive Drums 2 but the BFD player was included with my SSL interface bundle so I thought I'd give it a try. And yes, worth installing.
Easy to get to grips with and fast to use. While this doesn't have the bells and whistles of the flagship BFD software there's enough control and tweakability for me. I've got the factory kit plus a Pop Essentials (I think?) expansion and I've used both on demos with pleasing results. CPU load seems quite light, too, though I haven't measured it.
It's free, why not give it a try. I'm having fun with it.