I am sharing my thoughts here and few may disagree with me, but let me put it here.
If you ask for AMP-X vs AMP-Y, you will end up getting different answers. The reason is simple - Highly subjective.
Anyway, see if my suggestions here make sense :-
- Rotel RA 1070 is more powerful than Arcam A 19. If you are going to play tracks having high dynamics (e.g rock metal), then the simple answer is Rotel. More the power, better the dynamics. In case if your listening level (loudness) is low or below moderate, Arcam should suffice.
- If you have plans to upgrade the speakers as well, having Rotel will make your choice bit easy (as you need not worry whether the chosen speakers can be driven easily by your amp).