I agree with most in this thread- selection of components can take care of a lot of bass issues. Your B&W's are excellent speakers. They roll off at what, 38 Hz? Good for most everything except pipe organs. However, another consideration that affects bass, be it good or bad, is the room. It's much more difficult to compensate for room acoustics. Big, huge space, you're gonna have some issues with bass. Some would say the biggest factor is in fact the listening space. I think that's a fair statement. I had to have a subwoofer when I went to monitors. The music was thin sounding without it. But you have to find something that's going to integrate well into your system- something that's fast, flexible and will "disappear", otherwise, you'll just have a deep, annoying thump augmenting (or interfering with) the B&W's. You've got to find your own sweet spot, what appeals most to you. "Musicality" is a very subjective term- what sounds good to you is "musical" and it may sound like garbage to someone else. I had a sub before the JL that just kind of tossed a low "hum" out there, and it was indeed annoying. The JL doesn't do that for me. It blends. Some may think my system now sounds less musical, but that's their opinion. I'm the one that listens to it every day, just as you do with your rig. Music, cars, your guitar amp that you prefer- those are YOUR tastes. In the long run, isn't that all that really matters to you? A friend of mine plays guitar, and he despises tube amps for his axe. You prefer your tube amp for yours. See my drift here? You've received some very good choices for a sub in this thread, lots of options. Maineiac brings up the valid point of losing musicality with a sub. But, in the end, it's all up to what you think sounds best for your tastes. If you believe you need a subwoofer, go for it. They're your ears.
