We also have a 2004 DSDP, a 4009:
1-Not impressed with the new models as far as fit & finish of the woodwork.
2- The Freightliner chassis. We really like ours & the Spartan chassis.
Since ours has only 50,000 miles on it we have upgraded all the electronics, new tires & batteries & look forward to many years of RV'ing in it.