OK I tried an AMPEG SVT7 Pro with my Markbass 104HF - and its really good. The Ampeg gives a tight defined bottom end that the other amps didnt.
Comparing the 7 pro against the SVT-CL, the 7 pro has a similar heft to the low notes, and as the 7 pro only weights 7 Kg I can accept that weight (unlike the weight of a SVT-CL head. 40Kg). I'm impressed with the 7-pro - it has 95% of the tone of the SVT-CL. I set the levels so i was getting a little bit of overdrive on the loudest notes and it was sounding great
Unless I get the chance to try an Ampeg PN-410 Neo, I'll continue with this setup - I'm getting the tone I want and its light enough for me to move it anywhere.