Not all of a CPL has to be done on a complex - I think up to 20 hours can be done on a 'simple' single - although check the exact number of hours in LASORS. So long as you do the minimum hours required in the multi (or complex single if you were to do a SE CPL) you can do as many of the remainder in a simple aircraft as you like.
I do agree with everyone else though - if you can afford more hours do.
A word of warning though - I did SE CPL then MEP. A number of my good friends did ME CPLs. Unless you can afford alot of extra hours in the multi it is alot harder. If you do SE CPL you can concentrate on 'nailing' the CPOL aspects of the test instead of trying to learn to fly a multi aswell. Then on MEP you learn only how to fly the multi. CPL with assymentric etc ontop of the extra speed adds another dimention to the test.
I emphasise it is only my opinion - but it is chearper, and more importantly easier to do them seperate. However - if you want to go to that school because it is right for you, then that should have the final say.
JP