I appreciate it's probably not the best thing to say on an official Virgin forum, but I think the previous poster is probably better off looking at going with one of the main networks.
MVNOs in general target the budget end of the market, and if all you want is a bare basic calls/texts/data service and you have coverage, this is great and can save you a few ££ over the main networks. But the trade-off for that is that added extras and network-services aren't available. A bit like getting broadband from someone like TalkTalk rather than Virgin, as an extreme example.
It's not for this thread to give recommendations of any providers, but the previous poster is probably best off looking at a provider that offers these extras. Certainly WiFi calling, and ideally 4G calling too.
The problem is that the MNVOs use the EE coverage figures but in fact can't provide the EE coverage as my understanding is that they don't yet have access to 800 Mhz band.
In my area I got zero bars of 2g in most of the house & only 1 to 2 bars of 2g outside the house so I got a PAYGO sim from giffgaff (O2) & I get 3 to 4 bars of 4G everywhere in the house & 5 bars of 4G outside the house so I've swapped over to giffgaff.
I also got a PAYGO from 3 Mobile & that gave a good signal but lower than giffgaff.
Visitors on Vodafone have good signals as well.
I've not tried an EE PAYGO sim but I might do just to see.
The mobile signal where I live is very weak, depending on atmospheric conditions I get no or one bar on the signal indicator. I would like to take you up on your offer to provide information on how to improve my local signal strength.
@Doug4 wrote: The mobile signal where I live is very weak, depending on atmospheric conditions I get no or one bar on the signal indicator. I would like to take you up on your offer to provide information on how to improve my local signal strength.
Your best bet is to compare with local neighbours and suchlike which networks others are on. It's best to compare with people on the main networks (i.e. EE, 3, Voda or O2) where possible. In a high-proportion of cases, the coverage from a reseller/MVNO will be the same as that of the main network. But there are circumstances where this can differ. And in circumstances where you have good coverage outdoors but just struggle inside, then you are going to find yourself (sooner or later) wanting a WiFi-based calling and/or texting solution that makes all the difference.