Even if they use fairly cheap, low-grade components, they do nevertheless appear to be remarkable value for money.
Indalo, it's worth pointing out that the components (I'm excluding frame/battery/motor here) on the Sirocco are virtually the same as those on the Wisper 905SE City which is a highly regarded bike, in fact the Sirocco's RST CAPA forks have more travel than the Wisper's RST VITA forks and the Sirocco has branded Wellgo pedals rather than imitations. I'm not sure about the derailleur, but even if it's Tourney there's very little difference between Alivio and Tourney, they're both budget level. Brakes on both are Tektro but the Sirocco states rim and disk like the Wisper, but the photos clearly show two rim brakes so I'm not sure what's going on there.