Any review of MPs' pay and expenses by MPs themselves will be a sham. Any review by any body directly accountable to MPs will likewise be a sham. Any review that starts with a presumption of MPs' equivalency to the nations most senior professions rather than the nation's median (i.e. representative) occupations will be a sham.
Only a Royal Commission has any hope of coming up with a balanced and publicly acceptable solution to the stinking cesspit of sleaze and corruption that the Commons has become.