We have a 2003 Alpine 38FDDS. Previously owned Foretravel and Safari DP's.
Yes, they are the sports car of motorhomes. The Peak chassis is unique to Alpine, though of course the major components are pretty standard.
Long wheelbase to overall length ratio.
4 ride height valves, not 3.
Good front/rear weight distribution
Side radiator.
Engine on the 2000 will be the Cummins C. Then the ISL was an option and later, standard. Obviously the ISL 400 HP with engine compression brake was a sought after option. No more fuel consumption at the same speeds, but HP on tap if you need it.
As with any coach that age, some could be pristine, others well worn.