First of all, I have 2001 X5 3.0 with 5 speed and enjoy it very much. Coming from 440 hp S4 6 spd and 540i6, I can attest that CDV on X5 probably would not do much difference. On X5 clutch feels very strong and grabby (unlike 540) strait from the factory. Also, X5 is not ment to be driven like 540 or S4.
Regarding power: My basic package, no sunroof, K&N equipped 3.0 drives almost as fast as old 282hp 4.4. Low gearing in manual realy surprised me. Good luck