I've had a 2004 Thumb BO 4 for several years now using DR Hi-Beams. I love the sound of this bass, but I wanted a 5 string. I bought a 2005 model online figuring it wouldn't sound that much different, but it is much more different sounding than I expected. It has a thinner, more nasally tone. I'm trying different strings and EQ settings to try to normalize the differences. I ordered some DR FatBeams thinking that might fatten up the sound a bit but I won't have them for another couple of days, and I'm using quite a bit of mid-cut at 500Hz. It's getting closer, but I thought someone out there might have some ideas.