I've had a Metro R5/24 for over 4 years, and love this bass, but I have made some changes so it works better for me, some of which were intended to address the same issues raised by the OP.
First a few hardware suggestions...
If you don't have the VTC, then get it as a retrofit by all means. I did this on my 5-24 metro when I first got it, and the kit was ridiculously cheap - like $75.00 at the time.
Consider switching from Pan/Volume to Volume/Volume. While I sometimes miss having a master volume knob, I love the microcontrol over tonal options. Some of those shadings can give you a bit more of the mid-lift you mention.
Finally, if you're looking for more old-school thump, try to find a set of the Nordstrand-sourced big single pickups as a retrofit for the older 5-24 soapbars. I made this final move about 6 months ago, and am very happy with the results. More fundamental and low-mid punch. A little less "songful" when soloing in the upper register, but still quite good in that respect. Makes the bass less specialized and better able to cover a traditional Fender presence, with minimal sacrifice of the characteristics that make the 5/24 Modern distinctive.
Beyond bass hardware, several other posters have noted the amp question - I'm thinking it's less a question of which amp, and more an issue of the mid-range settings you use.
And how high do you have the preamp controls on the bass? If dialed back to minimal levels, or flat, you get more mid. Passive is also pretty middy, although I have to say that passive with the big singles is more successful than with the original soapbars. Again, the VTC is your friend...
I have a second Sadowsky, an NYC P/J 5/24, but other than it being lighter and having a 1 3/4" nut, I can't tell you it's any "better" than the optimized Metro. In fact, I had a friend over yesterday who has strong slap technique (I'm mostly fingerstyle), and I was thrilled by how good the Metro 5/24 sounded. I also think the 5/24's consistently have better B-strings than other Sadowskys - I've had my Metro 5/24 side by side with NYC Sadowskys, including another 5/24, and it saw all of them off.
For me, the 5/24 is a very special bass (I totally dig the ergonomics), and a new or used 5/24 Metro provides exceptional value. It's worth some work to see if you can make it work for you!
WWJD...What Would Jamerson Do?
Last edited by Joebone : 12-31-2012 at 10:59 AM.