I haven't run the JB3's internal AD, but I have run the h1xx series internal AD (which has been reported as the same). I doubt that anyone here will tell you that the internal AD on the JB3 is better than the AD20. Although I run my digi mod UA5 99% of the time, it is mainly due to the ease of an all in one box. I really like my AD20 because it gives a nice warm sound, IMO. Keep in mind that the AD20 is a pre / AD combo that has a minimum of 17db gain (verify this, but I'm 99% sure). I think you would need to drop the ST-9100 out of the chain and maybe use it for your stealth rig. I think the overall concensus would be that to get the most noticeable listening change out of the gear chain, it would involve changing the mic's.