Personally I don't think anyone of them is any better then the other... It's all in how you use it. I use FL because it's simple to use and you have everything you need. It comes with a wide variety of samples plus VST plugins you can get also. If you can't find the effect you need, then you create it using one of the Major generators they have. Sytrus for example is easy to use and you can make ANY sound you can think of if you know how to it to its maximum efficincy.
It's decent for recording if you have the right equipment and the vocorder can pretty much cover any effect you would need for your voice/instrument.
Now, I can't say much for MIDI because I have never used it MAJORLY with FL, but from what I have done, it seemed to handle it well.
so all in all, it doesn't really matter what program you use, it's how you use it. You can buy the best program money has to offer but if you don't know how to use it you mght as well be working with playstations MTV Music Generator. Stick with something that is versitile and can be use in any situation. I only use FL because I have no need for anything else at the moment. I've been looking into Reason, though, because the Drum synths are kinda iffy in FL and Reason has some sick drums.