Speaking from the wife's experience with 3, I would say the CS are dishonest, may just be that it's because it is outsourced and they don't have sufficient checks in place to ensure there is decent quality.
I would also be a little skeptical about network issues, 3 are decommissioning sites after the network sharing deal with T mobile, could well be that the area was covered by 3 but now is no longer covered or has not had a capacity upgrade.
Dave