Took test drive of skoda kylaq today and was disappointed

I took test drive of automatic version. I was looking to upgrade from elite i20 for my mom. The car has good ride quality and good punch but what annoyed me was the refinement, there was constant knocking noise coming from the engine when I highlighted this to skoda executive he said since it's a 3 cylinder engine at low speed the sound may come but at higher speeds it won't be an issue.Having driven the i20 n line it felt more refined and even the gear shifts felt smoother in the i20 thanks to the dct when compared to kylaq. I was about to finalize i20 n line and was a getting a good deal but then I came across few posts which mentioned notorious unreliability of hyundai's dct. All said and done I think for the city a NA engine shall serve better, leaning towards amaze cvt and i20 ivt.