Income tax audit under section 44ab and 44ad

Thank you very much in advance 

An assesee is having turnover as under

As per Profit and loss account                 Rs 88 lakhs (EXCLUDING TAXES) where

As per sales register                               Rs 1.2 crores ( INCLUDING TAXES) 

Q.1 Turnover Excluding Taxes or Turnover including taxes is to be considered  for audit u/s 44AB ? 

Q.2  If assesee selects section 44AD, turnover limit for audit is Rs 2 Crores and he will not be liable for audit  . Is there any benefits in opting section 44AD as comared to section 44AB.?