I feel the Dolphin of that era was a good bang for the buck. A better built coach then many, good materials and content, finish paint job.
I think they came in both Workhorse with 8.1 or F53 with the 6.8. I feel either of those chassis is a good one in those model years. (Believe the cutover to the improved 5spd Auto was in 2005 chassis year. Its a good transmission
If the Workhorse, and if that chassis was in the years of the Workhorse/Bosch pointing of fingers - beside the recall has been done on the front brakes.
Also IMO, National drained their financial resources pretty heavily when the took care of the coaches that had delimitation problems from the supplier of bad materials. Many manufactures did not take care of their customers with these problems. Just after the $$ bleeding to take care of these, the recession hit... Who knows, they may have made it if they too had not done the right thing fro their customers... All my opinion and I admit it is mostly from second hand info...
Best of luck to you, and happy hunting,