I have a ( PIONEER DEH-4200UB ) head unit currently in my 3rd gen...
I am able to control my 10'' ( RE SXX 10D2 ) with pretty good control...
the hu basically has a built in bass knob. I have the ability to fine tune the bass settings in about 5 different ways...
I wouldnt say that its the greatest hu out there, but for the price I am extremely happy with the level of contol I have...