You may want to check out this thread if you haven’t already:
There are a number of videos showcasing the A4 that might help give you a sense of what can be achieved with it. I don’t have the XD, but I love my A4. It’s an incredibly deep instrument. While it can certainly get nasty, it’s equally capable of beautiful, flowing pad sounds (for example). I use it for bass sounds a lot. A really fun and inspiring instrument.