We bought an '04 Tropical T350 a year ago. The only problem worth mentioning was with the bedroom slide. The gearbox has a brass gear in it that doesn't stand up to abuse. If there is a rhythmic noise when opening or closing the bedroom slide, the gear could be damaged. Our's failed after our second trip. The brass gear is still produced, but the shaft diameter has to be drilled out to fit the slide gearbox. Otherwise, it is a simple repair.
The solar panel on our rig is non-functional and looks badly weathered, but at 8+ years, I don't know if I would have expected anything different.
A year later, we are very happy with our purchase.
'04 National TropiCal T350
Behind the coach: