It's free, it looks great and it's got a lot of knobs. For this reason it was one of the first compressor plugs I ever tried out. A couple of years later and I'm still astonished by this thing. Don't think because it's free that in some way inferior to a compressor with a huge price tag. This is up there with the most advanced software compressors ever created.
Variable attack envelopes, mid/side effects, high pass on the sidechain, optional warm saturation, knee shape, upsampling and parallel. There really isn't an option left out. It's also the only compressor I've ever seen that has a mid-scoop eq. Not sure why you'd really need one built into the compressor but I've come to like it being there.
My only critique is that it doesn't really allow you to do a huge squish. Even when you max out the ratio and threshold it still sounds fairly civilized.
The only problem you might have is that you find it too versatile. If you're a rank beginner you probably don't need to start with Molot.