I'll give you my opinion....
I owned the Hammond XM2/XMc2, which is supposedly (as marketed by Hammond) an XK1 in a rack (
LINK ). I did not like the leslie, it had no depth nor presence in the mix. I used a Ventilator for the leslie. I also despised the chorus/vibrato. It was way too warbly, C3 was so warbly that it was unusable. I moved to C2, then eventually settled on C1, then out the door. The C/V ruined the vibe for me. At the time I purchased it I thought it would be an upgrade to my Voce V5+. At the end of the day I ended up keeping the Voce V5+ and selling the Hammond; I thought that the Voce sounded closer to my B3 and although the Voce doesn't have the greatest C/V I found it to be more pleasing than the Hammond. So I wouldn't give the Hammond a high grade.
I have never heard the Vox keyboard amp so I have no opinion other than to say that it has an 8" woofer. How is the bass response of this amp? Leslie speakers are essentially lo-fi speakers so it is not necessarily an advantage to having a hi fidelity speaker to drive a Hammond clone through as the Leslie speaker itself is not hi fidelity. However a typical tube leslie like a 122 or 147 leslie has a 15" woofer and the cabinet is large allowing for some pretty deep bass response. I don't know how the Vox would hold up reproducing the low end of the hammond tone. The only way to know for sure is to give it a try and judge for yourself.