"It's great multi-tasking phone and most importantly it accomodates two SIMs simultaneously. However, There is one thing lacking in this phone though and that is "You can Not make a call from your second sim while having your first sim set to default". what I mean is that with this phone you can choose your say O2 sim as your default sim and vodafone as slave sim.and in this case you can recieve calls on both O2&Vodafone numbers but you can only make calls using your default sim (i.e. O2). And in order to make calls from your second sim (i.e. vodafone) you have to set vodafone as your default sim from the sim management options before you can make a call using our vodafone sim. and this requires the phone to be rebooted prior to using 2nd sim!!! How annoying isn't it? Its Samsung we are talking about here, Come on even a cheap chinese branded phone can make calls from both sims without having to reboot the phone!!! Well thats the only bad point I have noticed in this phone. Otherwise its the best branded phone you can buy which runs 2 sims...All the best. Regards"