The Avia Guide's tones are 20db below reference, hence the 85db you need to use. The Outlaw's tones are 30db below reference: thus you use 75db. Setting it at 80 just means you haven't achieved reference at 0db. It won't hurt anything for sure.

Reference = 105db max at the listening position at 0 db when properly calibrated (115db from the LFE). Very few subs can hit the LFE reference.