So this is really down to how an MVMO works...
MVMOs buy bulk time/data on an ongoing basis from networks at a certain rate with minimum amounts etc... so they need to shift anything they agree to. The price of this is fairly low, after all - they bought it in bulk. Networks who resell get guaranteed custom through the MVMO so they arn't too worried and the service is already setup - to a large degree its "cheap" to add people to the network. All said and done it's a numbers game and currently - a race to the bottom. SIMO is really competitive too so these price points are not all that un-expected. It makes up a fraction of the market compared to PAYM/PAYG(provided SIM). The shift to higher end handsets has hurt SIMO too, people don't feel so happy with buying a £400 device and a £10PCM SIMO when they can do £30. Even if the TCO of the SIMO is cheaper.
