Hi,
I think the taps in Aldi have plastic head which is coated with a chrome effect. I have a friend who has these taps and the coating has worn off and chipped in places. When i was getting my kitchen i went for Franke and to be honest have had no problems. I think there is another brand of similar quality which i looked at called Blanco. I know that both are widely available from Kitchen showrooms.
The handset part is very lightweight and first impression, it feels like plastic - but the underside of the box states "Chrome plated, solid brass mixer tap"????