We have several N-series Nokias and are using Hypercard 3G from 2-phones-in-1
Sofar very reliable, full 3g/HSDPA signal and the standbye time is almost same as without the card.
I can highly recommend this company.
Our company is one of the whole sales dealers in the island and if you are looking for big order then i can arrange your requirement with 2 years guarantee. we have many types of dual Sim mobile. contact me if you think is favorable.