Sprint operates two nationwide networks. Depending on the device and the services it provides you could be using the CDMA network or the iDEN network that is mostly used for prepaid phones and direct connect.
Sprint itself also has a CDMA voice and data roaming agreement with Verizon, which MVNOs and subsidiary brands do not benefit from.
Virgin Mobile uses Sprint's CDMA network. Sprint has very good coverage in most major cities and along most interstate highways. That covers most of most peoples' lives, except the relatively small percentage of Americans in rural areas.
Virgin only uses iDEN. That's why their coverage is ass. You could be standing in line sight of a tower and have zero connectivity because that tower isn't supported.
http://en.wikipedia.org/wiki/Virgin_Mobile_USA"wireless voice, messaging and broadband data services to subscribers throughout the United States via the Sprint Nextel CDMA PCS network"
http://en.wikipedia.org/wiki/Boost_Mobile"Boost Nationwide Unlimited (AKA Monthly Unlimited Plan), which differs from their previous UNLTD plans, is offered for iDEN handsets as of January 22, 2009 and CDMA as of January 2010"
The reason you have sucky coverage is the PRL list is much more limited for Virgin phones and they don't allow roaming. Update the list and get better signal.
that isn't true, they are on the sprint cdma towers. Boost is their pre-paid brand that's on iden. Virgin won't roam on to verizon, though, which sprint handsets will.
Sprint itself also has a CDMA voice and data roaming agreement with Verizon, which MVNOs and subsidiary brands do not benefit from.