I ran 4061s>AD20 for about 2 years and then made the switch to the 4061s>mod SBM1 for a few reasons: the mod SBM1 combo sounded better to my ears, the SBM1 is slightly smaller and you need fewer cables (if you run a portable Sony deck), much easier to set levels in stealthy situations with the SBM1, ‘over’ lights on the SBM1 also help tremendously when running stealth. Hope this helps...