if you previously had experience with an aftermarket setup, you will probably be let down. i have the b&o and i can 100% tell you that it doesnt hit as hard as an aftermarket system. (maybe just as hard as a cheap one..)
its nice having a usable trunk and trunk space though.
I would say you need to go the aftermarket route. I would describe the B & O Play setup as a neutral European sound. It reminds me more of the sound I got with the ADS setup I put in my cars up through the early 2000's. I really like it for the kind of music I listen to but I can see where someone wanting a heavy low end would be disappointed.
I find it a little too boomy. By that I mean it gives you a lot of mid-to-high bass but no low bass. Like a boombox. I had to turn it down in the settings, and boost the mid and treble to try to get some brightness out of the sound.
BTW, I grew up on high fidelity stereo equipment, so that's where I'm coming from.